CN100584967C - Method for separating highly-pure rare-earth oxide from rare earth mine for reinforced baking by sulfuric acid - Google Patents

Abstract

The invention discloses a full-separating method of high-purity rare earth oxide from rare earth rare earth ore reinforced and sintered by sulfuric acid, which is characterized by the following: producing La2O3, Ce2O3, Pr5O11, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb4O7, Dy2O3 and Y2O3 through ultrasonic extracting-electrochemical quantivalence-changing synthetic separating technique; oxidizing Ce3+ into Ce4+; reducing Eu3+ into Eu2+ t oseparate from other tervalent rare earths.

Description

Full method of separating high purity rare earth oxides from vitriol intensified roasting rare earth ore deposit

Technical field:

The present invention relates to the separation in vitriol intensified roasting rare earth ore deposit, belong to the hydrometallurgy field.

Background technology:

It is that the rare-earth mineral ore deposit of mixing of monazite (bastnasite or the bastnasite with) is mixed continuous roasting under 300～800 ℃ temperature in rotary kiln afterwards with the vitriol oil that sulfuric acid roasting method decomposes rare-earth mineral, element such as rare earth and thorium generates soluble sulphate, fluorite changes the dense calcium of sulphur and the volatile gases hydrogen fluoride or the silicon fluoride of indissoluble into, and mineral such as iron, manganese also decompose to some extent and change into vitriol.Rare-earth mineral can directly be used the water extraction rare earth after handling through sulfuric acid roasting method.The industrial process of leaching rare earth is with through the material water extraction behind the sulfuric acid baking at present, owing to contain impurity such as iron, phosphorus, manganese, thorium in the infusion, therefore must purify.Classical purifying method is to add sodium-chlor and sodium sulfate in infusion, rare earth is precipitated out with impurity with the form of rare earth sulfuric acid sodium double salt to be separated, the rare earth sulfuric acid sodium double salt that is precipitated out is converted into the oxyhydroxide of rare earth with 20%～30% the caustic soda aqueous solution after washing, with hydrochloric acid the rare-earth hydroxide dissolving is formed rare-earth chloride solution, further carry out the packet transaction of rare earth element then, through separation and purification, obtain rare earth oxide product or rareearth enriching material.

The method of separation of rare earth elements has double salt precipitation method and fractional-distillation extraction, but the main at present extraction process that adopts.With P204 or P507 is extraction agent, is thinner with kerosene, lucium extraction can be divided into light-heavy rare earths group in acid system, light, in, three groups of heavy rare earths, light, in light, in four groups of heavy, heavy rare earths.The principle of grouping is certain aqueous phase acidity and a percentage extraction of control, under different acidity, P204 or P507 are different with the complex ability of rare earth element, control certain acidity and can make it have certain percentage extraction and stripping rate, and rare earth element just can be by predetermined boundary grouping.

The boundary of typical three component groups and acidity control scope are as follows: with P204 is extraction agent, and samarium-neodymium grouping: washing lotion acidity is concentration of hydrochloric acid 0.5～1.2mol/L, separation factor β _Sm/NdBe 5～12; Samarium-gadolinium grouping, washing lotion acidity is concentration of hydrochloric acid 1.5～2.0mol/L, separation factor β _Gd/SmBe 3～3.5; Gadolinium-terbium grouping, washing lotion acidity is concentration of hydrochloric acid 2.0mol/L, separation factor β _Tb/GdBe 5～6.The concrete fractionation extraction grouping flow process of its rare earth element is that feed liquid middle-weight rare earths chloride concentration is 1-1.2mol/L, feed acidity is pH=4-4.5, the P204 kerosin that consists of 1.0mol/L of organic phase, the acidity of washing lotion is concentration of hydrochloric acid 0.8mol/L, carries out neodymium-samarium grouping.It contains the raffinate of rare earth elements such as lanthanum, neodymium, generate rare earth chloride with in the ammonia and back condensing crystal, the organic phase of rare earth elements such as its load gadolinium, dysprosium is carried out the grouping extraction of gadolinium-dysprosium again, the concentration of extraction agent still is the P204 kerosin of 1.0mol/L, the acidity of washing lotion is concentration of hydrochloric acid 2.0mol/L, water after the extraction forms middle-weight rare earths carbonate with the yellow soda ash precipitation.The organic phase that the extraction back generates is stripped with 5.0mol/L hydrochloric acid, generates yttrium and heavy rare earths chloride product.

Divide the flow process of group rare-earth to compare with the double salt precipitation method has many good qualities with the P204 fractionation extraction, the fractionation extraction method of grouping has been simplified technology and has been realized the production serialization, exempted the heavy physical labor of operations such as double salt precipitation, alkali conversion, can produce light, in, the heavy rare earths product, enlarged Comprehensive Utilization of Rare, can directly directly be connected mutually again, further separate purification again, and this technology also reduce " three wastes " with following step fractionation extraction process.

It is the processing method of extraction agent extracting and separating rear earth element that Japanese documentation (spy opens clear 54-93672) has been introduced with P507, for the speed of accelerating to divide into groups, needs to add phase separation agent, prevents the generation of emulsification and third phase.With P507 is that the advantage of extraction agent is that reextraction acidity is low, is easy to strip, and separation factor is bigger than P204 between some rare earth element.

Chinese patent (CN 1009332B) has been introduced the metallurgical technical process that waits with 2-ethylhexyl phosphoric acid single 2-ethyl hexyl (hereinafter to be referred as P507) separation of rare earth elements in packet header.This technology is to be raw material with the rare earth chloride, the muriatic concentration of its feed liquid middle-weight rare earths is 240～250g/L, material liquid pH is 2-3, organic phase consists of 50%P507-50% kerosene (volume ratio), washing lotion acidity is 1.2-1.3mol/L hydrochloric acid, at first carrying out the grouping of neodymium-samarium, is that grouping that extraction agent carries out praseodymium-neodymium, cerium-praseodymium, lanthanum-cerium, samarium-europium, gadolinium-terbium successively separates and obtains products such as Neodymium trioxide, Praseodymium trioxide, cerium oxide, lanthanum trioxide, Samarium trioxide and heavy rare-earth oxide again with P507.

Chinese patent (CN 1009332B) has been introduced the Beijing Non-Ferrous Metal Research General Academy and has been handled packet header rare-earth mine sulfuric acid reinforcement sinter process.This strengthens sinter process, by improving maturing temperature, prolongs roasting time, makes impurity such as phosphorus in the ore, thorium, iron form materials such as sl. sol. phosphoric acid salt, then with this roasting material of water extraction.The acidity of infusion is 0.05～0.15mol/L sulfuric acid, with in calcium oxide or the lime carbonate and infusion, in the solution iron, phosphorus, thorium of trace respectively with forms such as ironic hydroxide, tertiary iron phosphate, thorium hydroxide, thorium phosphate further precipitation remove, and obtain pure rare earth sulfuric acid solution with separated from impurities.If with P204 or P507 is that extraction agent is connected mutually with the technology of hydrochloric acid system fractionation extraction grouping separation of rare earth elements, just must pass through transformation process, it is the muriate of rare earth that rare earth sulfuric acid solution is made the transition, the method of transition is to be in the sulphuric acid soln of 4-5 at pH, with the lipid acid or the naphthenic acid that contain 5 carbon to 9 carbon is extraction agent, kerosene is that thinner extracts, and is the strippant generation rare earth chloride of stripping with the hydrochloric acid of 5.0mol/L again.

Chinese patent (CN 1009332B) has been introduced the technology and the method for extracting and separating rear earth element from sulfuric acid system at the problem that existed in the former sepn process.This technology and method are the infusions that will make with sulphating roasting rare earth mine, use in the magnesium oxide and purification, obtain purified rare earth sulfate solution, carry out fractionation extraction with the P204 kerosin again, the concentration of mishmetal＜50g/L rare earth oxide in the feed liquid.The concentration of extraction agent is less than 2mol/L.This invented technology can make heavy rare earths enriched substance (Eu in samarium, europium, the gadolinium etc. ₂O ₃11%, Sm ₂O ₃-50%, Eu ₂O ₃The rate of recovery is about 99%, thick Neodymium trioxide (Nd ₂O ₃/ RE ₂O ₃＞85%) and product such as lanthanum cerium chloride.Thick Neodymium trichloride can be made the raw material of high-performance magnet neodymium iron boron, and this invented technology is saved transition, and work such as extraction agent saponification greatly reduce the cost of product.

Can find that from present documents and materials the extraction and separation technology of China Rare Earth Separation technology, particularly rare earth has reached world lead level.But the rare earth in the rare-earth mineral generally is the forms such as carbonate, fluorochemical, phosphoric acid salt, oxide compound or silicate that are insoluble in water.Must rare earth be converted into the compound of water-soluble or mineral acid by various chemical transformation, through dissolving, operation such as separate, purify, concentrate, make various mixed rare earth compounds, as product or separate the raw material of single rare earth.Decomposing the resulting mixed rare earth compound in back separation and Extraction from rare-earth mineral, to go out single pure rare earth element be more complicated and difficulty in chemical technology.Its reason mainly contains two: the one, and physical properties and chemical property between the lanthanon are quite similar, most rare earth ion radiuses occupy between adjacent two elements, all three stable valence states in the aqueous solution, the avidity of rare earth ion and water is big, because of being subjected to the protection of hydrate, its chemical property is closely similar, separates the very difficulty of purifying; The 2nd, rare-earth mineral is decomposed the impurity element more (as uranium, thorium, niobium, tantalum, titanium, zirconium, iron, calcium, silicon, fluorine, phosphorus etc.) of association in the resulting mixed rare earth compound in back.

Therefore, in the technical process of separation of rare earth elements, not only to consider the separation between the extremely close rare earth element of these tens chemical property, but also must consider that rare earth element is with the separation between the impurity element of association.The wet process technique separation method that adopts in the Rare Earth Production mainly contains now: (1) method of fractional steps (fractionation crystallization, precipitation classification and oxidation reduction process); (2) ion exchange method; (3) solvent extration.

Hydrometallurgy belongs to chemical metallurgical method, whole process is among solution, the solvent mostly, adopts chemical separation technological processs such as precipitation, crystallization, redox, solvent extraction, ion-exchange exactly as the separation and the leaching process of the decomposition of rare-earth mineral, rare earth oxide, rare earth compound, single rare earth metal.Use organic solvent extractionprocess more generally now, it is the common processes of industrial separation high-purity single rare earth element.Though hydrometallurgy flow process complexity, product purity height, the finished product wide application of production.

The main flow of Rare Earth Separation is extraction process, ion exchange method and fractionation crystallization at present.Preceding two kinds of methods are discontinuous on process, and cost is very high, and the rare earth element purity that extracts is also lower, can not adapt to large-scale industrial production.Extraction process is to utilize material to have the characteristics of different solubilities in different solvents, carries out a kind of method of separating substances.China has all reached very high level at the research of extraction theory, the synthetic and aspects such as application and the isolating extraction process flow of rare earth element of novel extraction agent.Its extraction process of solvent extration separates method with fractionation precipitation, fractional crystallization, ion-exchange etc. and compares, have good separating effect, throughput big, be convenient to quick continuous production, be easy to realize series of advantages such as control automatically, thereby become the main method of extensive rare-earth separating gradually.

Solvent extration is a kind of important chemical separation means, and it has advantages such as selectivity is good, mass transfer is fast, separation efficiency is high, treatment capacity is big, operation is continuous, equipment is simple, has become the main method that domestic and international single rare earth is produced.The rare-earth smelting factory of China substantially all adopts P504, P507 and naphthenic acid extraction to be the single rare earth separation process of agent technology, in conjunction with P507 extration resin chromatograph, ion-exchange chromatography, separation technology such as redox, can produce purity is the single rare earth product of 4～5N.The extraction process that in separation process, has a collection of unique properties, level advanced person.Can think like this that rare ten minutes of China occupies international prostatitis from state of the art.The separating device of the solvent extration of industrial application has mixer-settler, centrifugal extractor etc. at present, and the used extraction agent of purification rare earth has: the cation extractant such as P204, the P507 that with the acid phosphoric acid ester are representative; With amine is the anionresin liquid N1923 of representative; And neutral phosphates such as TBP, P350 are the solvent extraction agent of representative.The viscosity of these extraction agents and proportion are all very high, and is not easily separated with water.Usually with the kerosene equal solvent its dilution back is used.The extraction process process generally can be divided into three main phase: extraction, washing, reextraction.

But extraction is as the industrial separation technology, and by the test of production practice, it still exists the chemical technology and the engineering problem of further research of many need and solution.Also there are problems in existing rare earth extraction separation of produced flow process, as the quality instability, and the cost height, energy consumption is big, and the disposal of waste gas, water and industrial residue amount is big, extraction agent " poisoning " etc.This has just proposed more, higher requirement to the technological method and the equipment of extracting and separating, must have new efficient, easy Rare Earth Separation flow process (comprising the significant improvement to existing industrial production flow process) to satisfy the needs of high-tech material to single high-purity or ultra-pure rare-earth products.Subject matter has:

(1) problem of extraction system

Optimize the selection of extraction system, key is extraction agent.P507 (2-ethylhexyl phosphoric acid single 2-ethyl polyhexamethylene) is better than P204 (2-ethylhexyl phosphoric acid dibasic acid esters) to the average separation factor (β is 2.2～2.4) of rare earth element, is effective extraction agent of extracting and separating rear earth, but also has the following disadvantages:

1. to be difficult to back extraction complete for heavy rare earth element reextraction acid concentration height, particularly scandium;

2. the right separation factor (β) of some elements is less, as Nd/Pr, and Gd/Eu, Er/Y, the β value of Lu/Yb etc. is between 1.4～1.8;

3. in hydrochloric acid or sulfuric acid medium, heavy rare earths ionic extraction rate is slower, and the time that reaches extraction equilibrium is longer, can influence the raising and the economic benefit of productivity.

(2) problem of extraction equipment

At present the major equipment of extracting and separating is a mixings-clarifying tank, mixings-clarifying tank have to the variation adaptability of comparing flow velocity by force, characteristics such as easy handling, be the general extraction equipment of employing in China's Rare Earth Production.In industrial production, in order to guarantee cell body high stage efficiency is arranged, often want the residence time of accretion at mixing section, increase settling time simultaneously, cause the cell body cumulative volume to increase.Generally, the volume ratio of clarifying chamber and mixing section be 2.5～3.0 this mainly be that dispersion particle is little, be difficult to assemble phase-splitting.In order to improve separation efficiency and to reduce the cell body effective volume, Chinese scholars has been done many improvement to the design of mixer-settler extractor in recent years, is the research of many interlayers as separating mixing section, and the static coacervation can quicken phase separation etc.

Therefore, how accelerating the extraction rate of industrial extraction system, is the throughput that improves factory, one of key issue that reduces cost.

(3) linking between technology and " three wastes " problem

The Rare Earth Production flow process is to be formed by different separating technology optimum combination.Being connected between mutual linking between extraction process and extraction process and follow-up other technology, wherein arranged.Except the linking of raffinate water as feed liquid, key issue is that the technology of organic phase outlet component is connected.Because raffinate and strip liquor rare earth concentration are lower, the acidity height, generally adopt in the alkali and after, heat spissated way and handle the back and use.This way is the energy consumption height not only, and a large amount of spent acid can not obtain reclaiming, complicated operation, equipment loss is big, and contaminate environment, and produce new " three wastes,.Therefore, study that continuous, easy feed liquid concentrates and deacidification technology is the key that separating technology is connected, adopt that to precipitate back extraction be one of valid approach.

Therefore, improve the rare earth recovery utilization rate, reduce consuming, what enhance productivity is the problem that the rare earth extraction process presses for solution.

Summary of the invention:

The objective of the invention is to propose full method of separating high purity rare earth oxides from vitriol intensified roasting rare earth ore deposit, adopt in supersonic leaching-ammonia and purification-ultrasonic extraction-electrochemistry is appraised at the current rate-chemical treatment combined separation technology, isolate high-purity Ce ₂O ₃, La ₂O ₃, Pr ₂O ₃, Nd ₂O ₃, Sm ₂O ₃, Eu ₂O ₃, Gd ₂O ₃, Tb ₄O ₇, Dy ₂O ₃Be Y ₂O ₃

By isolated all kinds of rare-earth products, have the advantage of high quality, high stability by the present invention, competitive power is very strong, and is good before the economic benefit.

Of the present invention from vitriol intensified roasting rare earth ore deposit full method of separating high purity rare earth oxides, it is characterized in that: in the using ultrasound leaching-ammonia and purification-ultrasonic extraction-electrochemistry appraise at the current rate-chemical treatment combined separation technology, separate high purity rare earth oxides Ce entirely ₂O ₃, La ₂O ₃, Pr ₂O ₃, Nd ₂O ₃, Sm ₂O ₃, Eu ₂O ₃, Gd ₂O ₃, Tb ₄O ₇, Dy ₂O ₃And Y ₂O ₃, comprise following processing step:

(1) supersonic leaching: in the supersonic leaching device, be that leaching agent leaches operation, the rare earth in the vitriol intensified roasting rare earth ore deposit is leached, separate, obtain the rare earth sulfuric acid salts solution through solid-liquid with the aqueous sulfuric acid that contains rare earth in water or the technology;

(2) neutralization purifies: in stirring and in the refining plant, with in ammonia or the alkaline earth metal oxide and purify, separate through solid-liquid, remove non-rare earth impurity, make purified rare earth sulfate solution;

(3) ultrasonic extraction grouping: in the ultrasonic extraction device, be extraction agent with P204, kerosene is that thinner extracts grouping, and water is a light rare earths vitriol enriched substance; The organic phase rare earth sulfate enriched substance of attaching most importance to; Water goes further separating treatment, and organic phase enters (8) and goes on foot further separating treatment;

(4) electrochemical oxidation: the water vitriol enriched substance solution that previous step obtains enters in the anolyte compartment of electrochemical reactor, under acidic conditions, and the Ce in the earth solution ³⁺Be oxidized to Ce ⁴⁺, produce Ce (SO simultaneously ₄) ₂Precipitation is separated through solid-liquid, and liquid phase enters next step processing; Solid phase is the cerous sulfate crude product, and the cerous sulfate crude product obtains cerium oxide product through washing, dissolving, purification, precipitation and calcination;

(5) electrochemical reduction: previous step is separated in the cathode compartment of electrochemical reactor that the non-cerium lree enrichment liquid obtain enters previous step through solid-liquid, under acidic conditions, and the trivalent europium Eu in the earth solution ³⁺Be reduced into divalent europium Eu ²⁺After, produce europous sulfate EuSO ₄Precipitation is separated through solid-liquid, separates with other trivalent rare earth, and liquid phase enters next step further separation and purification; Solid phase is the europous sulfate crude product, and the europous sulfate crude product obtains the europium sesquioxide product through washing, dissolving, purification, precipitation and calcination;

(6) ultrasonic extraction fractionation grouping: previous step is non-cerium and europium light rare earths solution through the isolating liquid phase of solid-liquid, and this solution enters in the ultrasonic extraction apparatus for grouping, with La ₂O ₃Content is that the sulfuric acid raffinate of 17-28g/L is a feed liquid, regulate its pH to 1-5, kerosene is that thinner extracts grouping, P204 content is 1.0-1.5mol/L in the organic phase, volume ratio between organic phase and the water is 1-3: 1, carry out counter-current extraction, obtaining water is the lanthanum enriched substance, and the lanthanum enriched substance obtains the lanthanum trioxide product through washing, dissolving, purification, precipitation and calcination;

(7) ultrasonic fractionation extraction separates: previous step is praseodymium-neodymium enriched substance and gadolinium-terbium enriched substance through the organic phase of counter-current extraction, separate through further ultrasonic fractionation extraction, refining, washing, dissolving, purification, precipitation and calcination obtain Praseodymium trioxide, Neodymium trioxide, gadolinium sesquioxide and terbium sesquioxide;

(8) ultrasonic fractionation extraction grouping: the heavy rare earths vitriol pregnant solution that obtains with the ultrasonic extraction grouping of (3) step is a stock liquid, the organic phase that contains heavy rare earth element in samarium, gadolinium and the terbium in the extraction liquid, make the transition through solvent extraction, with hydrochloric acid is anti-stripping agent, rare earth sulfuric acid solution is converted into the rare-earth salts acid solution, from raffinate, removes Ca in the process of abstraction and type-reverting ²⁺, Mg ²⁺And Fe ²⁺Impurity, and make rare earth obtain enrichment by control strippant concentration and flow, in ultrasonic fractionation extraction apparatus for grouping, be stock liquid with the rare-earth salts acid solution that obtains; With the P507 ammonium salt of 0.2-0.7mol/L, the P507 of 0.8-1.5mol/L and the mixture of kerosene is extracted organic phase; Concentration of hydrochloric acid is 1.1-3.6mol/L in the washing lotion; Its volume flow is than being extracted organic phase: stock liquid: washing lotion=0.85-3.5: 1: 0.12-0.70, in this fractionation extraction grouping sepn process, the volumetric molar concentration of extracting phase middle-weight rare earths is 0.1-1.0mol/L, obtain gadolinium-terbium enriched substance and terbium-dysprosium enriched substance, be stock liquid with gadolinium-terbium enriched substance and terbium-dysprosium enriched substance respectively, further separation and purification is produced heavy rare earths oxygenated products in gadolinium sesquioxide, terbium sesquioxide and the enrichment dysprosium oxide.

In the present invention, the processing condition of described extracting operation are: solid-to-liquid ratio is 1000g: (8-30) L, and service temperature is 5-50 ℃, ultrasonication intensity is 0.2-20.0W/cm ², ultrasonic frequency is 19-80kHz.

In the present invention, described ultrasonic generating unit is any in probe type ultrasonic wave producer, vibrator type ultrasonic generator, the vibration plate formula ultrasonic generator.

In the present invention, in ultrasound-enhanced rare earth leaching-extracting technology, described ultrasonic leaching-extracting equipment is still formula extraction equipment or mixing-clarification formula extraction equipment or the tubular type extraction equipment that has heat-exchanger rig and whipping appts; Or continuous still formula extraction equipment or the mixing-clarification formula extraction equipment or the tubular type extraction equipment of heat-exchanger rig and whipping appts be not set.

In the present invention, in ultrasound-enhanced rare earth extraction process, ultrasonic extraction is simple extraction or fractionation extraction or grouping extraction; In ultrasonic fractionation extraction process, adopt polycomponent two outlet technology or polycomponent multiple exit fractionation cascade extraction technologies.

In the present invention, when carrying out fractionation grouping separation, the content of feed liquid middle-weight rare earths cerium oxide is 30-46g/L, and the acidity of feed liquid is pH=4 to 0.15mol/L sulfuric acid, the content of P204 is 0.5-1.5mol/L in the organic phase, and vitriolic concentration is 0.4-0.6mol/L in the washing lotion.

In the present invention, described electrochemical reactor is ordinary flat type electrochemical reactor or three-dimensional electrochemical reactor; The anolyte compartment and the cathode compartment of electrochemical reactor are isolated by barrier film; In the anolyte compartment of electrochemical reactor, carry out Ce ³⁺Oxidizing reaction, in cathode compartment, carry out Eu ³⁺Reduction reaction, or adopt 2 electrochemical reactors to carry out Ce respectively ³⁺Oxidation and Eu ³⁺Reduction.

In the present invention, in purified pure component earth solution, add ammonia, produce the oxyhydroxide crystalline deposit and separate out, separate through solid-liquid, get the precipitation of hydroxide thing and analyze,, repeat above-mentioned sepn process till reaching purity requirement if purity does not reach the requirement of product; Adopt dissolving with hydrochloric acid precipitation of hydroxide thing then, preparation purified hydrochloric acid earth solution; In purified salt acid rare earth, adopt gac or resin absorption, further remove impurity; Add bicarbonate of ammonia or volatile salt in purified salt acid rare earth solution, being deposited in the solid-liquid separator of generation separates, and the liquid phase of telling is further separated to obtain the single component rare-earth products; The solid phase product obtains the carbonated rare earth product 25-600 ℃ of drying, and the carbonated rare earth product obtains high-purity oxidation rare-earth products 600-1000 ℃ of following calcination; In order to improve the quality of separation and purification process and rare-earth products, in the precipitation of carrying out successively, crystallization, precipitation removal of impurities solid-liquid separation unit operation process, adopt ultrasound-enhanced process, the processing condition of ultrasound-enhanced process are: service temperature is 25-45 ℃, and ultrasonication intensity is 2.0-5.0W/cm ², ultrasonic frequency is 19-25kHz.

In the technological process of described continuous separation of rare earth elements, extraction agent uses through reprocessing cycle, in technical process, the utilization of the water yield is carried out the recycle except turning back to the unit process that is complementary with processing condition, satisfying under the condition of production technique, making the concentration of rare earth element in feed liquid high as far as possible, the unnecessary water yield adopts the concentration in the sepn process of vacuum multiple-effect evaporation method of enrichment raising rare earth element, solve waste water handling problem simultaneously, the implementation procedure cleaner production.

The pounds per square inch absolute (psia) of described feed liquid vacuum multiple-effect evaporation concentration operation is 0.001-0.008MPa.

The present invention is the combined utilization of following three kinds of methods and technology:

(1) liquid-solid supersonic leaching and liquid-liquid ultrasonic extraction technology

With ultrasound-enhanced liquid-solid leaching and liquid-liquid extraction process.In the supersonic leaching device, the rare earth in the vitriol intensified baked rare-earth mineral is leached; Separate through solid-liquid, obtain the rare earth sulfate solution mixture, the rare earth sulfate solution mixture is divided into groups and separate through ultrasonic extraction.Separate through the fractionation extraction grouping, water is light rare earths (cerium group) vitriol enriched substance; Organic phase is heavy rare earths (yttrium group) vitriol enriched substance.

Solvent extration is a kind of important chemical engineering separation means, and it has extracts and the separation efficiency height, be convenient to advantages such as operate continuously, throughput are big.For many years, a large amount of work has been done by China in rare earth production technology and theoretical investigation,, composition many at the rare earths material constituent element changes characteristics greatly, equivalent component, effective separation factor model and the fuzzy extraction and separation technology etc. of having researched and proposed the polycomponent Rare Earth Separation are optimized the method and the technology of cascade extraction processing parameter, and be abundant and developed the cascade extraction theory.But there is following problem in rare earth extraction sepn process at present main:

1. liquid-liquid extraction mixed problem: in the liquid-liquid extraction mixing process, blending dispersion is insufficient, and the rate of mass transfer of liquid-liquid phase is low, is difficult to reach fast microcosmic and mixes, and therefore, the speed of rare earth extraction mixing process is slow, efficient is low.

2. the mixed liquid of liquid-liquid extraction-liquid layering (i.e. clarification) problem: in the extraction separation process of rare earth, mixing is the primary condition of extract reallocation, and clarification then is the necessary process that extraction distributes.If mix fully, though the distribution capability of extraction is not fully exerted, dispersion particle is little, is difficult to assemble phase-splitting, has brought the problem of the inferior separating effect of the mixed liquid of liquid-liquid extraction-liquid delaminating process.Therefore, in traditional rare earth extraction sepn process, mixing and clarification are a pair of contradiction.How to pass through the reinforced rare earth extraction process, solve and to mix in the rare earth extraction process and clarify this contradiction, control the rerum natura such as particle diameter, size-grade distribution of rare earth effectively, researching and developing efficiently that abstraction technique has very important using value, is the key point of efficient, the economic rare earth extraction technology of exploitation.Document announcement and we studies show that, ultrasonic is the effective means of strengthening the chemical engineering process.From the fifties, some investigators of state such as the U.S., the former Soviet Union have reported ultrasonic in the chemical application in engineering research work of chemistry, thereby caused the very big interest of chemical chemical engineering and process engineering academia and industry member, ultransonic since then application from before the physics field expanded chemical field to.Ultrasonic applied research in chemical engineering processes such as extraction, crystallization, emulsification, precipitation and environmental improvement at present is subjected to people's attention day by day.

Characteristic of the present invention is that this process with great industrial applications background of slective extraction rare-earth separating system is a research system, adopts ultrasonic and extraction coupling rare-earth separating technology, has realized the breakthrough of extracting and separating rear earth process gordian technique.Its innovation part is the correlation effect that the using ultrasound cavatition produces, improve the dispersiveness of liquid-liquid extraction process, improve extraction rate of mass transfer and the clarification sepn process of extraction back, the Applied Physics technology fundamentally solves the isolating conspicuous contradiction of rare earth extraction, improve the efficient of rare earth extraction and the throughput of extraction equipment, reduction process energy consumption promotes the great-leap-forward development of China's rare earth extraction isolation technique.

Ultrasonic energy strengthening extraction (leaching) process, its effect mainly shows: ultransonic cavatition can produce liquid-liquid dispersion, reinforcing mass transfer and breakdown of emulsion etc.Ultrasonic wave mainly comes from hyperacoustic cavitation effect and microjet effect subsequently thereof to the influence of extraction process.It is ultrasonic that existing theory and practice can at home and abroad not appear in the newspapers but ultrasonic and extraction process coupling are applied to extraction (leaching) rare-earth separating process as yet for using for reference at aspects such as surface cleaning, Preparation of Catalyst, emulsion preparation and reinforcement electrochemistry.

(2) electrochemical oxidation-reduction technique: realize appraising at the current rate of rare earth element by electrochemical method.The electron structure of group of the lanthanides atom is (Xe) 4f ^0-145d ^0-16s ², after losing two 6s and 5d or 4f electronics, formed modal Lu ³⁺, La wherein ³⁺, Gd ³⁺And Lu ³⁺The 4f subgrade be respectively full sky, half-full or full up state.According to Hund, these states all are the most stable, so these three elements+3 valencys are the most stable.Be positioned at the Lu of their both sides ³⁺All have and obtain or lose electronics to reach or near the trend of aforementioned stable state.This just makes the series elements of calumniating that is positioned at La, Gd and Lu next door produce and appraises at the current rate.As Ce ³⁺, Pr ³⁺, Tb ³⁺And Dy ³⁺Form tetravalence, and Sm ³⁺, Eu ³⁺, Tm ³⁺, Yb ³⁺Then formed divalence.Utilize the character of appraising at the current rate of rare earth to separate, its separation efficiency is far above general ion-exchange and solvent extraction and separation.Applied Electrochemistry oxidation-reduction technology is with the Ce in the acid earth solution ³⁺Be oxidized to Ce ⁴⁺, will high price europium Eu ³⁺Be reduced into europium Eu at a low price ²⁺Thereby, separate with other trivalent rare earth.Utilize the character of appraising at the current rate of rare earth to separate, its separation efficiency is far above general ion-exchange and solvent extraction and separation.

(3) chemical treatment: be used for the precipitation and the calcination of dissolving, washing, purification and the pure solution of product of rare-earth mineral, adopt ultrasonic technique to strengthen chemical treating process simultaneously.Ultrasound-enhanced chemically treated principle is cavitation effect, mechanical effect and the heat effect that produces when utilizing ultrasonic wave to propagate in medium, strengthen solid phase in the dispersion of liquid phase, the Surface Renewal of solid-liquid interface, the material transfer between solid-liquid, thereby the strengthening extraction process, the speed and the efficient of raising Rare Earth Separation process.

Advantage of the present invention:

Advantage of the present invention is:

(1) to smelt rare-earth mineral with sulfuric acid strengthening roasting be raw material to technology of the present invention, in the using ultrasound leaching-ammonia and purification-ultrasonic extraction-electrochemistry appraise at the current rate-chemical treatment combined separation technology the technical process that directly is connected for the technology of separation of rare earth elements.

(2) technology of the present invention is provided with before separation of rare earth elements with in ammonia or the alkaline earth metal oxide and purify, separate through solid-liquid, remove non-rare earth impurity, make purified rare earth sulfate solution, with in the ammonia and purify, prevent to generate double salt of rare earth precipitation and calcium sulfate slag, and compare with the rate of recovery that has improved the scavenging process middle-weight rare earths in calcium oxide or the Paris white with purification, the quantity of slag has reduced by one times.

(3) in the extraction process owing to there is not the interference of silicon, fluorine, phosphorus and micro-flocculation agent, emulsification does not take place, guaranteed normally carrying out of extraction process and back sepn process.

(4) use P204 as extraction agent in sulfuric acid system, kerosene is that thinner carries out fractionation extraction grouping separation of rare earth elements, pH1～4 o'clock ratio separation factor β height between some rare earth element in hydrochloric acid system.

(5) because in the sulphuric acid soln of rare earth element, with P204 extraction agent when extracting, because gadolinium-terbium separation factor β value is bigger, grouping separates between gadolinium-terbium easily, so at first carry out ultrasonic extraction grouping separation between gadolinium-terbium.

(6) ultrasonic extraction: using ultrasound-extraction coupling technique, improve the dispersiveness of liquid-liquid extraction process, improve extraction rate of mass transfer and extraction back clarifying process, the Applied Physics technology fundamentally solves the mixing that exists in the rare earth extraction process and the contradiction of clarifying process, the speed of strengthening extraction process and efficient.

(7) electrochemistry is appraised at the current rate: adopt the valence state that exists of electrochemical oxidation-reduction technique control rare earth element, in same electrochemical reactor, in acid earth solution simultaneously with Ce ³⁺Be oxidized to Ce ⁴⁺, with trivalent europium Eu ³⁺Be reduced into divalent europium Eu ²⁺, make it to separate with trivalent rare earth, further improved isolating speed and efficient, improved the utilising efficiency of electrochemical reactor, reduced the consumption of energy simultaneously, also protected environment.Applied Electrochemistry oxidation-reduction technology is controlled the valence state that exists of rare earth element, can reduce chemical material consumption, reduce and pollute, improve and extract selectivity, alleviate rare earth and non-rare earth impurity segregational load, reducing rare-earth morphology and valence state transforms, make the reaction conditions trend gentle, this is for sufficiently and reasonably extracting and utilizing the rare earth resources of China's preciousness that significance is arranged.

(8) chemical treatment:, adopt ultrasonic technique to strengthen the chemical method sepn process simultaneously in the precipitation and the calcination of dissolving, washing, purification and the pure solution of product of rare-earth mineral.

Description of drawings:

Fig. 1, Fig. 2, technological process of production synoptic diagram of the present invention; Fig. 2 is the continuous figure of Fig. 1.

Embodiment:

Below in more detail the present invention is further described with embodiment, but the present invention is not subjected to the restriction of these embodiment.

Embodiment 1:

Main production equipments: stir the batch mixes still, supersonic leaching equipment, ultrasonic extraction equipment, the ionic membrane electrochemical reactor stirs the neutralization precipitation still, and ultrasonic crystallization kettle filters equipment for separating liquid from solid, pure water and pure sour equipment and analytical and testing instrument.

Main raw material: sulfuric acid, hydrochloric acid, liquefied ammonia, bicarbonate of ammonia, volatile salt, the P204 extraction agent, the P507 extraction agent, sulfuric acid strengthening roasting is smelted rare-earth mineral.

Processing step is as follows:

(1) supersonic leaching: in the 1L stirring tank, add entry, the concentrated sulfuric acid roasting material (mixed rare earth oxide content is greater than 30%) that takes by weighing the 45g rare-earth mineral adds in the supersonic leaching device, the employing ultrasonic frequency is 19.8kHz, the probe type ultrasonic producer instrument of 250W, above-mentioned material is added in the leacher of the logical cooling circulating water of 1000ml strap clamp cover, the probe of ultra-sonic generator instrument is placed this mixture, 40 ℃ of red-tape operati temperature, behind ultrasonication 20min, close ultrasonic apparatus, rare earth in the vitriol intensified baked rare-earth mineral is leached, obtain earth solution, leach liquor separates through solid-liquid, the rare earth sulfate solution that makes contains rare earth oxide 30～50g/L in this solution, phosphorus 0.1～0.5g/L, iron 1.0～2.0g/L, thorium 0.01～0.1g/L adopts the supersonic leaching technology can improve the leaching efficiency of leaching speed and rare earth.

(2) neutralization purifies: the feed liquid that previous step is obtained add stir in and in the refining plant, with ammonia is neutralizing agent, control pH value is 3.5-5.5, make non-rare earth impurity produce precipitation, separate through solid-liquid, make purified rare earth sulfate solution, the composition table that purifies forward and backward rare earth sulfuric acid solution sees 1, and the shared per-cent of various rare earth elements sees Table 2 in the rare earth sulfuric acid solution of purification back.

The composition of table 1 rare earth sulfuric acid solution

Table 2 purifies the shared per-cent of various rare earth elements in the rare earth sulfuric acid solution of back

Rare earth element	La 2O 3	CeO 2	Pr 6O 11	NdO 3	Sm 2O 3	Eu 2O 3	Gd 2O 3	Y 2O 3	Other
										Content/%	27.23	48.70	5.20	15.20	1.20	0.24	0.36	0.11	1.2-1.3

Oxide compound neutralization with ammonia or alkaline-earth metal, can make purified sulfuric acid rare earth feed liquid, separate in the purified rare earth sulfate solution process of preparation through solid-liquid, impurity elements such as phosphorus, iron, thorium must be removed from solution, make neutralizing agent with ammonia or basic metal oxygen oxide compound, certainly will produce the rare earth sulfuric acid double salt precipitation, cause the loss of rare earth element.If use calcium oxide or Paris white to purify rare earth sulfate solution, can avoid the generation of rare earth sulfuric acid double salt as neutralizing agent.But owing to generated calcium sulfate, the rate of recovery that the quantity of slag increases the absorption rare earth element decreases, so be the best with liquefied ammonia as neutralizing agent.Therefore, in the separation removal of impurities process of sulfuric acid rare earth feed liquid, before neutralization purifies, the solid-liquid sepn process is set, can significantly reduces the sedimentary amount of rare earth sulfuric acid double salt that produces, make neutralizing agent with ammonia simultaneously and can reduce the water yield in the sulfuric acid rare earth feed liquid system.

(3) ultrasonic extraction grouping: in the groove type ultrasonic extraction equipment, with two (2 one ethylhexyl) phosphoric acid is extraction agent, kerosene is thinner, is that raw material extracts grouping with further purified rare earth sulfate solution directly, and the concentration of mixed rare-earth oxide is less than 50g/L in the feed liquid.The operational condition of ultrasonic extraction is: service temperature is 35 ℃, and ultrasonication intensity is 2.0W/cm ², ultrasonic frequency is 19.8kHz, carries out the interrupted extraction grouping and separates. and separate through the fractionation extraction grouping, water is a cerium group light rare earths vitriol enriched substance; Organic phase is a yttrium group heavy rare earths vitriol enriched substance; Water enters next step processing, and organic phase enters the processing of (8) step.Employing ultrasonic extraction grouping, can significantly improve the speed of extraction grouping and the extraction grouping efficient of rare earth, adopt the ultrasonic extraction grouping can than traditional extraction packet rates improve 20-60 doubly this by separating technology in, because in the sulphuric acid soln of rare earth, be that extraction agent is when extracting with P204, gadolinium-terbium separation factor β value is bigger, and grouping separates between gadolinium-terbium easily, separates so at first carry out the ultrasonic extraction grouping between gadolinium-terbium.The ultrasonic extraction grouping of carrying out gadolinium-terbium separates, and its condition is containing rare earth oxide 30-46g/L in the feed liquid, and organic phase is that P204 content is the kerosin of 0.5-1.5mol/L, and washing lotion acidity is 0.4-0.6mol/L sulfuric acid.The stream ratio of organic phase, feed liquid, washing lotion is 1: 4～7: 0.3～0.4.Feed liquid middle-weight rare earths oxide content near the solubleness of rare earth element in sulphuric acid soln, occurs rare compound crystal precipitation that goes up greater than 46g/L easily, rare earth oxide content is less than 30g/L, follow-up extraction equipment is increased, and throughput reduces, so be good with the 30-46g/L rare earth oxide.The concentration of extraction agent P204 in kerosene increases the organic phase viscosity of formation greater than 1.5mol/L, and the phase-splitting difficulty less than 0.5mol/L, reduces throughput.Washing lotion acidity surpasses 0.6mol/L sulfuric acid, and the crystal of the vitriol of rare earth element is separated out, and washing lotion acidity is less than 0.4mol/L sulfuric acid, and washing effect is not good.Under given operational condition, the gadolinium that all can obtain-terbium grouping separating effect.The organic phase of discharging from countercurrent washing section last step is for containing heavy rare earth element heavy rare earths vitriol enriched substance such as gadolinium, dysprosium, organic phase middle-weight rare earths oxide content 3-6g/L; Water is a light rare earths vitriol enriched substance, and outlet aqueous phase rare earth oxide is 25-43g/L, and the concentration of its free acid is 0.08～0.13mol/L sulfuric acid.The sulfuric acid that this outlet water is called light rare earthss such as containing lanthanum, cerium, praseodymium, neodymium many liquid that come together.

(4) electrochemical oxidation: previous step water vitriol enriched substance solution enters in the anolyte compartment of electrochemical reactor, under acidic conditions, with the Ce in the earth solution ³⁺Be oxidized to Ce ⁴⁺, through the solid-liquid lock out operation, to separate with trivalent rare earth, liquid phase enters next step processing; Solid phase is the cerous sulfate crude product, and the cerous sulfate crude product obtains cerium oxide product through washing, dissolving, purification, precipitation and calcination.

(5) electrochemical reduction: previous step is separated in the cathode compartment of electrochemical reactor that the non-cerium lree enrichment liquid obtain enters previous step through solid-liquid, under acidic conditions, and the trivalent europium Eu in the earth solution ³⁺Be reduced into divalent europium Eu ²⁺After, produce the europous sulfate precipitation, separate through solid-liquid, separate with other trivalent rare earth.Liquid phase enters next step further separation and purification; Solid phase is the europous sulfate crude product, and the europous sulfate crude product obtains the europium sesquioxide product through washing, dissolving, purification, precipitation and calcination.

(6) ultrasonic extraction fractionation grouping:, be difficult with the method for the single-stage extraction separation of rare earth elements that divides into groups because the rare earth element chemical property is very similar.Therefore, adopt ultrasonic fractional-distillation extraction.The fractionation extraction system is made up of counter-current extraction section and countercurrent washing section, the last level of counter-current extraction section is as the charging level, the organic phase solution that contains extraction agent, enter the fractionation extraction system from the first step of counter-current extraction section, discharge from the last level of countercurrent washing section, washing lotion enters the fractionation extraction system from the prime of countercurrent washing section, discharge from the first step of counter-current extraction section with the water that raffinate forms, the feed liquid that contains rare earth element enters the fractionation extraction system from the last level of counter-current extraction section.Is that non-cerium and europium light rare earths solution enter in the ultrasonic extraction apparatus for grouping with previous step through the isolating liquid phase of solid-liquid, sulfuric acid raffinate with lanthanum rare earth oxide 17-28g/L is a feed liquid, regulate its pH to 1-5, kerosene is that thinner extracts grouping, P204 content is 1.0-1.5mol/L in the organic phase, organic phase: water is 1-3: 1, and carrying out counter-current extraction, can to obtain water be the lanthanum enriched substance, the lanthanum enriched substance obtains the lanthanum trioxide product through washing, dissolving, purification, precipitation and calcination.

(7) ultrasonic fractionation extraction separates: praseodymium-neodymium enriched substance and gadolinium-terbium enriched substance that previous step is obtained through the organic phase of counter-current extraction, praseodymium-neodymium enriched substance and gadolinium-terbium enriched substance is separated through further ultrasonic fractionation extraction, makes with extra care, washing, dissolving, purification, precipitation and calcination obtain producing Praseodymium trioxide, Neodymium trioxide, Samarium trioxide, gadolinium sesquioxide and terbium sesquioxide product.

(8) ultrasonic fractionation extraction grouping: the yttrium group heavy rare earths vitriol pregnant solution that obtains with the ultrasonic extraction grouping of (3) step is a stock liquid, the organic phase that contains heavy rare earth element in samarium, gadolinium, the terbium etc. in the extraction liquid, make the transition through solvent extraction, with hydrochloric acid is anti-stripping agent, and rare earth sulfuric acid solution is converted into the rare-earth salts acid solution.Can from raffinate, remove Ca in the process of abstraction and type-reverting ²⁺, Mg ²⁺And Fe ²⁺Impurity, and make rare earth obtain enrichment by control strippant concentration and flow.In ultrasonic fractionation extraction apparatus for grouping, with the rare-earth salts acid solution that obtains is stock liquid, P507 ammonium salt with 0.2-0.7mol/L, 0.8-1.5mol/L P507 and the mixture of kerosene be organic phase, concentration of hydrochloric acid is 1.1-3.6mol/L in the washing lotion, its volume flow is than being organic phase: stock liquid: washing lotion is 0.85-3.5: 1: 0.12-0.70, in this fractionation extraction grouping sepn process, the volumetric molar concentration of extracting phase middle-weight rare earths is 0.1-1.0mol/L, obtain gadolinium-terbium enriched substance and terbium-dysprosium enriched substance, be stock liquid with gadolinium-terbium enriched substance and terbium-dysprosium enriched substance respectively, further separation and purification is produced gadolinium sesquioxide, heavy rare earths oxygenated products in terbium sesquioxide and the enrichment dysprosium oxide.

Adopt this technology can obtain Ce ₂O ₃, La ₂O ₃, Pr ₂O ₃, Nd ₂O ₃, 1Sm ₂O ₃, Eu ₂O ₃, Gd ₂O ₃, Tb ₄O ₇, Dy ₂O ₃And Y ₂O ₃10 kinds of products and 2 kinds of middle enriched substance have realized making full use of of rare earth resources, and technical process is shorter, segregation rate and efficient height, and stable technical process, and operation is convenient, and the casting yield and the total yield of product are higher.

Embodiment 2: with the rare earth sulfuric acid solution after purifying as the fractionation extraction of the neodymium-samarium isolating feed liquid of dividing into groups, its concentrations of rare-earth is 45.38g/L, feed acidity is a 0.06mol/L sulfuric acid, organic phase is that P204 content is No. 260 solvent oil solvents of 1.0mol/L, washing lotion acidity is 0.572mol/L sulfuric acid, 4 grades of extraction sections, 7 grades of washing sections, totally 11 grades, the stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 66 milliliters: 5.5 milliliters, organic phase and water duration of contact are 6 minutes, 27 ℃ of extraction temperature, and the shared per-cent of each rare earth element is La in the feed liquid ₂O ₃27.53, CeO ₂49.70, Pr ₆O ₁₁5.13, Nd ₂O ₃15.44, Sm ₂O ₃1.20, Eu ₂O ₃0.23, Gd ₂O ₃0.33, Y ₂O ₃0.20. export the water of discharge the sulfuric acid raffinate that contains lanthanum, cerium, praseodymium, samarium from counter-current extraction section first step water, its rare earth concentration is the 41.33g/L rare earth oxide, the concentration of free acid is 0.114mol/L sulfuric acid, and the organic phase middle-weight rare earths concentration of discharging from the 7th grade of organic phase relief outlet of countercurrent washing section is the 3.82g/L rare earth oxide.Eu in the organic phase ₂O ₃The rate of recovery be 99.15%, organic phase is the enriched substance of heavy rare earth element in samarium, europium, the gadolinium etc., it consists of La ₂O ₃＜0.1%, CeO ₂＜0.1%, Pr ₆O ₁₁＜0.1%, Nd ₂O ₃0.1%, Sm ₂O ₃49.33%, Eu ₂O ₃11.92%, Gd ₂O ₃20.19%, Y ₂O ₃11.05%, water consist of La ₂O ₃27.53%, CeO ₂49.70%, Pr ₆O ₁₁5.13%, Nd ₂O ₃15.44%, Sm ₂O ₃1.20%, Eu ₂O ₃0.23%, Gd ₂O ₃0.37%, Y ₂O ₃0.20%.

Is that anti-stripping agent is stripped with the organic phase of load samarium, europium, gadolinium enriched substance with 5mol/L hydrochloric acid, the muriate enriched substance of the rare earth element of the samarium of water, europium, gadolinium etc., No. 260 solvent oil organic phases that contain P204 are return and are recycled).

Embodiment 3: its experiment condition is substantially with embodiment 4, and the concentration of different is feed liquid middle-weight rare earths is the 30.17g/L rare earth oxide, and the acidity of feed liquid is 0.05mol/L sulfuric acid; The stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 99 milliliters: 5.5 milliliters, extraction temperature is 23 ℃.The aqueous phase rare earth concentration of discharging from the water outlet is the 27.89g/L rare earth oxide.The concentration of its free acid is 0.089mol/L sulfuric acid, and the organic phase middle-weight rare earths concentration that organic phase comes from discharge is the 3.92g/L rare earth oxide.Consist of Nd in the organic phase ₂O ₃＜0.1%, Sm ₂O ₃51.23%, Eu ₂O ₃11.55%, the composition La of water ₂O ₃28.21%, CeO ₂50.80%, Pr ₆O ₁₁5.23%, Nd ₂O ₃16.35%, Sm ₂O ₃＜0.1%, Eu ₂O ₃The rate of recovery be 100.12%, Nd ₂O ₃The rate of recovery is 99%.

Embodiment 4: the face condition is substantially with embodiment 5 in fact, and the concentration of different is feed liquid middle-weight rare earths is the 35.26g/L rare earth oxide, and the acidity of feed liquid is 0.06mol/L sulfuric acid; The stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 84 milliliters: 5.5 milliliters, extraction temperature is 28 ℃.The aqueous phase rare-earth oxidation substrate concentration of discharging from the water outlet is 32.34g/L.The concentration of free acid is 0.096mol/L sulfuric acid, and the concentration of the organic phase middle-weight rare earths that the organic phase outlet is discharged is the 4.05g/L rare earth oxide.Consist of Nd in the organic phase ₂O ₃＜0.1%, Sm ₂O ₃51.75%, Eu ₂O ₃11.32%; Water consist of La ₂O ₃28.06%, CeO ₂50.7%, Pr ₆O ₁₁5.32%, Nd ₂O ₃16.56%, Sm ₂O ₃＜0.1%, Eu ₂O ₃The rate of recovery be 99.3%).

Embodiment 5: its experiment condition is substantially with embodiment 6, and the concentration of different is feed liquid middle-weight rare earths is the 40.56g/L rare earth oxide, and the stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 75 milliliters: 5.5 milliliters. and extraction temperature is 21 ℃.The aqueous phase concentrations of rare-earth of discharging from the water outlet is the 37.16g/L rare earth oxide.The concentration of free acid is 0.104mol/L sulfuric acid, and the organic phase middle-weight rare earths concentration that the organic phase outlet is discharged is the 4.10g/L rare earth oxide.Organic phase consist of Nd ₂O ₃＜0.1%, Sm ₂O ₃51.31%, Eu ₂O ₃11.54%, water consists of La ₂O ₃28.03%, CeO ₂50.96%, Pr ₆O ₁₁5.30%, Nd ₂O ₃16.31%, Sm ₂O ₃＜0.1%.

Embodiment 6: its experiment condition is substantially with embodiment 4, and the concentration of different is feed liquid middle-weight rare earths is the 45.00g/L rare earth oxide, and washing lotion acidity is 0.556mol/L sulfuric acid; The stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 100 milliliters: 4.8 milliliters, the aqueous phase rare earth concentration of discharging from the water outlet is the 42.60g/L rare earth oxide.The concentration of its free acid is 0.091mol/L sulfuric acid, and the organic phase middle-weight rare earths concentration that the organic phase outlet is discharged is the 5.90g/L rare earth oxide.Organic phase consist of Nd ₂O ₃0.27%, Sm ₂O ₃48.16%, Eu ₂O ₃12.10%, water consists of La ₂O ₃27.90%, CeO ₂50.45%, Pr ₆O ₁₁5.31%, Nd ₂O ₃16.52%, Sm ₂O ₃＜0.1%.

Embodiment 7: its experiment condition is substantially with embodiment 4, and the concentration of different is feed liquid middle-weight rare earths is the 45.00g/L rare earth oxide, and the acidity of washing lotion is 0.556mol/L sulfuric acid; The stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 100 milliliters, the aqueous phase rare earth concentration of discharging from the water outlet is the 42.07g/L rare earth oxide, and the concentration of its free acid is 0.09mol/L sulfuric acid; The organic phase middle-weight rare earths concentration that the organic phase outlet is discharged is the 5.92g/L rare earth oxide.Organic phase consists of Nd ₂O ₃＜0.1%, Sm ₂O ₃49.51%, Eu ₂O ₃11.95%; Water consists of La ₂O ₃28.08%, CeO ₂50.62%, Pr ₆O ₁₁5.27%, Nd ₂O ₃16.52%, Sm ₂O ₃0.11%.

Embodiment 8: with the water of neodymium-samarium fractionation extraction discharge, the sulfuric acid raffinate that promptly contains lanthanum, cerium, praseodymium, neodymium is as praseodymium-neodymium isolating feed liquid of dividing into groups, to pH4, its rare earth concentration is the 40.55g/L rare earth oxide with this feed adjustment, and wherein the shared per-cent of each rare earth element is as follows:

La ₂O ₃27.02, CeO ₂51.42, Pr ₆O ₁₁5.45, Nd ₂O ₃16.62, Sm ₂O ₃0.14, Eu ₂O ₃＜0.1, other＜0.1.

Adopt following condition to carry out the fractionation extraction separation and produce thick Nd ₂O ₃, organic phase is that P204 content is No. 260 molten machine oil organic solvents of 1mol/L, washing lotion acidity is 0.56mol/L sulfuric acid, 13 grades of extraction sections, 7 grades of washing sections.The stream ratio of organic phase, feed liquid and washing lotion is 20 milliliters: 10 milliliters: 6.5 milliliters.The time that organic phase contacts with water is 6 minutes.Extraction temperature is 25 ℃.The water of discharging is the sulfuric acid raffinate that contains lanthanum, cerium, and its rare earth concentration is the 20.71g/L rare earth oxide, and the concentration of its free acid is 0.27mol/L sulfuric acid.Water consists of La ₂O ₃35,16%, CeO ₂59.78%, Pr ₆O ₁₁3.39%, Nd ₂O ₃2.20%.From the organic phase that the 7th grade of organic phase relief outlet of countercurrent washing section discharged, it consists of La ₂O ₃＜0.1%, CeO ₂3.22%, Pr ₆O ₁₁9.29%, Nd ₂O ₃86.73%, Sm ₂O ₃1.60%.The organic phase of the thick neodymium of load is stripped with 5mol/L hydrochloric acid, get the muriate of thick neodymium, organic phase is returned and is recycled.

Embodiment 9: its experiment condition is substantially with embodiment 10, and the stream ratio of different is organic phase, feed liquid and washing lotion is 20 milliliters: 10 milliliters: 7.0 milliliters.The rare earth concentration of discharging water is the 20.27g/L rare earth oxide, and the concentration of free acid is 0.26mol/L sulfuric acid, and water consists of La ₂O ₃33.25%, CeO ₂57.83%, Pr ₆O ₁₁4.93%, Nd ₂O ₃4.40%; Organic phase consists of La ₂O ₃＜0.1%, CeO ₂1.22%, Pr ₆O ₁₁5.17%, Nd ₂O ₃92.35%, Sm ₂O ₃2.06%.

Embodiment 10: its experiment condition is substantially with embodiment 10, and different is that feed acidity is pH1.3,17 grades of extraction sections, 14 grades of washing sections.The stream ratio of organic phase, feed liquid and washing lotion is 15 milliliters: 10 milliliters: 4.5 milliliters.Discharging the water rare earth concentration is the 23.24g/L rare earth oxide, and the concentration of its free acid is 0.28mol/L sulfuric acid.Water consists of La ₂O ₃36.81%, CeO ₂59.84%, Pr ₆O ₁₁2.25%, Nd ₂O ₃1.34%; Organic phase consists of La ₂O ₃＜0.1%, CeO ₂3.11%, Pr ₆O ₁₁12.8%, Nd ₂O ₃82.97%, Sm ₂O ₃1.60%.

Adopt this technology can obtain Ce ₂O ₃, La ₂O ₃, Pr ₂O ₃, Nd ₂O ₃, Sm ₂O ₃, Eu ₂O ₃, Gd ₂O ₃, Tb ₄O ₇, Dy ₂O ₃, Y ₂O ₃Deng 10 kinds of products and 2 kinds of middle enriched substance; Technical process is shorter, and stable technical process, and operation is convenient, and equipment is easy to solve and maintenance; The casting yield and the total yield of product are higher.

Claims (10)

1, a kind of from vitriol intensified roasting rare earth ore deposit full method of separating high purity rare earth oxides, it is characterized in that: in the using ultrasound leaching-ammonia and purification-ultrasonic extraction-electrochemistry appraise at the current rate-chemical treatment combined separation technology, separate high purity rare earth oxides Ce entirely ₂O ₃, La ₂O ₃, Pr ₂O ₃, Nd ₂O ₃, Sm ₂O ₃, Eu ₂O ₃, Gd ₂O ₃, Tb ₄O ₇, Dy ₂O ₃And Y ₂O ₃, comprise following processing step:

(1) supersonic leaching: in the supersonic leaching device, be that leaching agent leaches operation, the rare earth in the vitriol intensified roasting rare earth ore deposit is leached, separate, obtain the rare earth sulfuric acid salts solution through solid-liquid with the aqueous sulfuric acid that contains rare earth in water or the technology;

(2) neutralization purifies: in stirring and in the refining plant, with in ammonia or the alkaline earth metal oxide and purify, separate through solid-liquid, remove non-rare earth impurity, make purified rare earth sulfate solution;

(3) ultrasonic extraction grouping: in the ultrasonic extraction device, be extraction agent with P204, kerosene is that thinner extracts grouping, and water is a light rare earths vitriol enriched substance; The organic phase rare earth sulfate enriched substance of attaching most importance to; Water goes further separating treatment, and organic phase enters (8) and goes on foot further separating treatment;

(4) electrochemical oxidation: the water vitriol enriched substance solution that previous step obtains enters in the anolyte compartment of electrochemical reactor, under acidic conditions, and the Ce in the earth solution ³⁺Be oxidized to Ce ⁴⁺, produce Ce (SO simultaneously ₄) ₂Precipitation is separated through solid-liquid, and liquid phase enters next step processing; Solid phase is the cerous sulfate crude product, and the cerous sulfate crude product obtains cerium oxide product through washing, dissolving, purification, precipitation and calcination;

(5) electrochemical reduction: previous step is separated in the cathode compartment of electrochemical reactor that the non-cerium lree enrichment liquid obtain enters previous step through solid-liquid, under acidic conditions, and the trivalent europium Eu in the earth solution ³⁺Be reduced into divalent europium Eu ²⁺After, produce europous sulfate EuSO ₄Precipitation is separated through solid-liquid, separates with other trivalent rare earth, and liquid phase enters next step further separation and purification; Solid phase is the europous sulfate crude product, and the europous sulfate crude product obtains the europium sesquioxide product through washing, dissolving, purification, precipitation and calcination;

(6) ultrasonic extraction fractionation grouping: previous step is non-cerium and europium light rare earths solution through the isolating liquid phase of solid-liquid, and this solution enters in the ultrasonic extraction apparatus for grouping, with La ₂O ₃Content is that the sulfuric acid raffinate of 17-28g/L is a feed liquid, regulate its pH to 1-5, kerosene is that thinner extracts grouping, P2O4 content is 1.0-1.5mol/L in the organic phase, volume ratio between organic phase and the water is 1-3: 1, carrying out counter-current extraction, to obtain water be the lanthanum enriched substance, and the lanthanum enriched substance obtains the lanthanum trioxide product through washing, dissolving, purification, precipitation and calcination;

(7) ultrasonic fractionation extraction separates: previous step is praseodymium-neodymium enriched substance and gadolinium-terbium enriched substance through the organic phase of counter-current extraction, separate through further ultrasonic fractionation extraction, refining, washing, dissolving, purification, precipitation and calcination obtain Praseodymium trioxide, Neodymium trioxide, gadolinium sesquioxide and terbium sesquioxide;

(8) ultrasonic fractionation extraction grouping: the heavy rare earths vitriol pregnant solution that obtains with the ultrasonic extraction grouping of (3) step is a stock liquid, the organic phase that contains heavy rare earth element in samarium, gadolinium and the terbium in the extraction liquid, make the transition through solvent extraction, with hydrochloric acid is anti-stripping agent, rare earth sulfuric acid solution is converted into the rare-earth salts acid solution, from raffinate, removes Ca in the process of abstraction and type-reverting ²⁺, Mg ²⁺And Fe ²⁺Impurity, and make rare earth obtain enrichment by control strippant concentration and flow, in ultrasonic fractionation extraction apparatus for grouping, be stock liquid with the rare-earth salts acid solution that obtains; With the P507 ammonium salt of 0.2-0.7mol/L, the P507 of 0.8-1.5mol/L and the mixture of kerosene is extracted organic phase; Concentration of hydrochloric acid is 1.1-3.6mol/L in the washing lotion; Its volume flow is than being extracted organic phase: stock liquid: washing lotion=0.85-3.5: 1: 0.12-0.70, in this fractionation extraction grouping sepn process, the volumetric molar concentration of extracting phase middle-weight rare earths is 0.1-1.0mol/L, obtain gadolinium-terbium enriched substance and terbium-dysprosium enriched substance, be stock liquid with gadolinium-terbium enriched substance and terbium-dysprosium enriched substance respectively, further separation and purification is produced heavy rare earths oxygenated products in gadolinium sesquioxide, terbium sesquioxide and the enrichment dysprosium oxide.

2, according to the described method of from vitriol intensified roasting rare earth ore deposit, separating high purity rare earth oxides entirely of claim 1, it is characterized in that: the processing condition of extracting operation are: solid-to-liquid ratio is 1000g: 8-30L, service temperature is 5-50 ℃, and ultrasonication intensity is 0.2-20.0W/cm ², ultrasonic frequency is 19-80kHz.

3, according to the described method of separating high purity rare earth oxides from vitriol intensified roasting rare earth ore deposit entirely of claim 1, it is characterized in that: described ultrasonic generating unit is any in probe type ultrasonic wave producer, vibrator type ultrasonic generator, the vibration plate formula ultrasonic generator.

4, according to the described method of from vitriol intensified roasting rare earth ore deposit, separating high purity rare earth oxides entirely of claim 1, it is characterized in that: in ultrasound-enhanced rare earth leaching-extracting technology, described ultrasonic leaching-extracting equipment is still formula extraction equipment or mixing-clarification formula extraction equipment or the tubular type extraction equipment that has heat-exchanger rig and whipping appts; Or continuous still formula extraction equipment or the mixing-clarification formula extraction equipment or the tubular type extraction equipment of heat-exchanger rig and whipping appts be not set.

5, according to the described method of separating high purity rare earth oxides from vitriol intensified roasting rare earth ore deposit entirely of claim 1, it is characterized in that: in ultrasound-enhanced rare earth extraction process, ultrasonic extraction is simple extraction or fractionation extraction or grouping extraction; In ultrasonic fractionation extraction process, adopt polycomponent two outlet technology or polycomponent multiple exit fractionation cascade extraction technologies.

6, according to the described method of from vitriol intensified roasting rare earth ore deposit, separating high purity rare earth oxides entirely of claim 1, it is characterized in that: when carrying out fractionation grouping separation, the content of feed liquid middle-weight rare earths cerium oxide is 30-46g/L, the acidity of feed liquid is pH=4 to 0.15mol/L sulfuric acid, the content of P204 is 0.5-1.5mol/L in the organic phase, and vitriolic concentration is 0.4-0.6mol/L in the washing lotion.

7, according to the described method of separating high purity rare earth oxides from vitriol intensified roasting rare earth ore deposit entirely of claim 1, it is characterized in that: described electrochemical reactor is ordinary flat type electrochemical reactor or three-dimensional electrochemical reactor; The anolyte compartment and the cathode compartment of electrochemical reactor are isolated by barrier film; In the anolyte compartment of electrochemical reactor, carry out Ce ³⁺Oxidizing reaction, in cathode compartment, carry out Eu ³⁺Reduction reaction, or adopt 2 electrochemical reactors to carry out Ce respectively ³⁺Oxidation and Eu ³⁺Reduction.

8, according to the described method of from vitriol intensified roasting rare earth ore deposit, separating high purity rare earth oxides entirely of claim 1, it is characterized in that: in purified pure component earth solution, add ammonia, producing the oxyhydroxide crystalline deposit separates out, separate through solid-liquid, getting the precipitation of hydroxide thing analyzes, if purity does not reach the requirement of product, repeat above-mentioned sepn process till reaching purity requirement; Adopt dissolving with hydrochloric acid precipitation of hydroxide thing then, preparation purified hydrochloric acid earth solution; In purified salt acid rare earth, adopt gac or resin absorption, further remove impurity; Add bicarbonate of ammonia or volatile salt in purified salt acid rare earth solution, being deposited in the solid-liquid separator of generation separates, and the liquid phase of telling is further separated to obtain the single component rare-earth products; The solid phase product obtains the carbonated rare earth product 25-600 ℃ of drying, and the carbonated rare earth product obtains high-purity oxidation rare-earth products 600-1000 ℃ of following calcination; In order to improve the quality of separation and purification process and rare-earth products, in the precipitation of carrying out successively, crystallization, precipitation removal of impurities solid-liquid separation unit operation process, adopt ultrasound-enhanced process, the processing condition of ultrasound-enhanced process are: service temperature is 25-45 ℃, and ultrasonication intensity is 2.0-5.0W/cm ², ultrasonic frequency is 19-25kHz.

9, according to the described method of from vitriol intensified roasting rare earth ore deposit, separating high purity rare earth oxides entirely of claim 1, it is characterized in that: in the technological process of above-mentioned continuous separation of rare earth elements, extraction agent uses through reprocessing cycle, in technical process, the utilization of the water yield is carried out the recycle except turning back to the unit process that is complementary with processing condition, satisfying under the condition of production technique, make the concentration of rare earth element in feed liquid high as far as possible, the unnecessary water yield adopts the concentration in the sepn process of vacuum multiple-effect evaporation method of enrichment raising rare earth element, solve waste water handling problem simultaneously, the implementation procedure cleaner production.

10, according to the described method of separating high purity rare earth oxides from vitriol intensified roasting rare earth ore deposit entirely of claim 9, it is characterized in that: the pounds per square inch absolute (psia) of feed liquid vacuum multiple-effect evaporation concentration operation is 0.001-0.008MPa.

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