DE2407677A1 - PROCESS FOR THE PRODUCTION OF OXYGEN COMPOUNDS OF ANTIMONE WITH METALS - Google Patents

Description

The present invention relates to processes for the preparation of the oxygen compounds of antimony with metals more precisely, a process for the preparation of the oxygen compounds of pentavalent antimony with metals.

It is known that the oxygen compounds of antimony with metals of groups IB, HA, IIB, HIA, IHB, IVA, IVB, ' VA, VB, VIB, VIIB and VIIIB of the periodic table as catalysts for the production of acrylonitrile by oxidizing Ammonolysis of propylene can be used. The acrylonitrile is used as a raw material for the production of synthetic Fibers, plastics and rubber.

The catalysts, which are based on the oxygen compound

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fertilize antimony with metals from the groups listed above of the periodic table can be used to oxidize olefins to unsaturated aldehydes and Acids, e.g. for the oxidation of acrolein and methacrolein to acrylic and methacrylic acids, as well as for the oxidation of olefin / ammonium / mixtures to the unsaturated nitriles and the catalytic dehydrogenation of olefins to diolefins use.

Some oxygen compounds or solid solutions of antimony and tin can also be used as a material for the manufacture of Resistors are used, which are used in electronic technology.

The known processes for the preparation of the oxygen compounds of antimony with metals are the following: Treatment of a mixture of elemental antimony and corresponding metal with nitric acid and oxidizing the mixture of the compounds produced with oxygen or an oxygen-containing gas under heating.

Another method is the heat treatment of the mixtures of antimony oxides and metal oxides or hydroxides. The heat treatment is carried out in the presence of when heating decomposing substances such as ammonium chloride, ammonium nitrate, urea salts, etc.

Yet another method of making the oxygen compounds of antimony with metals forms the oxidizing one

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Heat treatment of mixtures of organic and mineral salts of antimony with organic or mineral metal salts.

It is also a process for making the oxygen compounds of antimony with metals known, in which a joint precipitation of .Antimony oxides and metal oxides or -hydroxides in an aqueous medium from their salts by means of a base and the oxidizing heat treatment of these Way produced mixed precipitate in the presence of oxygen or of an oxygen-containing gas used will.

It is also a method of melting a nitric acid Hydrate metal compound known with the addition of one or more antimony oxides, followed by a heat treatment the reaction mass is carried out in the presence of oxygen or an oxygen-containing gas.

The hydrolysis of chlorine compounds of antimony with the corresponding metals with subsequent isolation is also used by means of hydrochloric acid and the oxidizing heat treatment of the mixed precipitate produced in this way in Presence of oxygen or an oxygen-containing gas.

What is common to all the processes mentioned for the production of the oxygen compounds of antimony with metals consists in the processing of an antimony pentoxide, for example by treatment of metallic antimony with nitric acid, hydrolysis of antimony pentachloride, oxidation of antimony trioxide with Nitric acid, oxidizing a solution of antimony trichloride with

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Hydrogen peroxide or nitric acid, etc.

The next stage consists in the reaction of the antimony pentoxide prepared according to the process outlined above with Metal compounds that are produced by mixing antimony pent-

oxide is realized with metal compounds and by subsequent oxidizing heat treatment.

Of the processes mentioned for the preparation of the oxygen compounds of antimony with metals, the process which is based on the oxidation of antimony compounds is particularly widespread (the compounds of metallic antimony, antimony trioxide, etc.) with nitric acid with the addition of a metal compound, e.g. Iron nitrate with subsequent precipitation of the mixture produced with ammonia, filtration and washing out of the precipitate, which then dried for a long time and through. leads is based.

This process was described in U.S. Patents 3,546,138, 3,197,419, 3,200,081, 3,200,084, 3,198,750, 3,341,471; GB-PSs 3 244 642, 3,152,570, 3,309,325, 3,346,513; Japanese patents No. 282 171 336 856, 340 131; in Belgian patent specification No. 189,769 and in French patent specification No. 1,168,279.

The oxygen compounds of antimony and iron (see US-PS'e No. 3 197 419 and No. 3 546 138) are produced by the oxidation of metallic antimony, antimony trioxide, antimony tetroxide produced with heated concentrated nitric acid, the

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Oxidation is carried out until the development of red nitrogen oxides ceases. An aqueous solution of iron nitrate is then added, and the mixture produced is precipitated using the ammonium hydroxide to a pH of 7.6-8.0. The precipitate thus produced was filtered and washed, then durchgeglüht at a temperature of 120 ° and then dried at temperatures between 800 and 900 ⁰ C.

Before the precipitation, the mixture becomes a 30% colloid Solution of silicon dioxide, which increases the strength of the material to be manufactured, as well as activating additives, e.g. rhenium nitrate added. The material produced is used as a catalyst.

The oxygen compounds of antimony and manganese (see US-PS No. 3 20Q, 081.) are produced by the oxidation of crushed metallic antimony with heated concentrated nitric acid until the evolution of nitrogen oxides ceases and the resulting suspension is then mixed with a manganese nitrate solution produced, after which it is precipitated with an ammonia solution.

The mixture prepared is calcined at 120 ⁰ C dried within 12 hours at 425 ⁰ C after which the mixture is again durchgeglüht within 12 hours at 76o ⁰ C in an open oven.

In US-PS No. 3,200,084 a process for the preparation of an oxidizing antimony-cerium catalyst is

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wrote, which consists in oxidizing the crushed metallic antimony with nitric acid at its boiling temperature until the development of nitrogen oxide vapors ceases, mixing it with a solution of cerium nitrate and precipitating it by adding a 28% ammonia solution, after which the precipitated product is precipitated filtered off, washed with water by letting a stream of air through the precipitated product during each washing process, and then drying the precipitated product at a temperature of 120 ⁰ C, annealing at a temperature of 425 ⁰ C and at a temperature of 76O ⁰ C in an open Oven activated.

The disadvantages of the known processes for the preparation of the oxygen compounds of antimony with metals include their multi-stage nature, the presence of a large amount of production waste in the form of sewage and the harmful ones Gas evolution.

When oxidizing metallic antimony with nitric acid, e.g. around '900, only nitrogen oxides per 1 ton of metallic are produced Developed antimony.

When washing the joint precipitated mixture of iron and antinion hydroxides, 40 m of wastewater are produced per 1 t of dry substance. This wastewater is contaminated with antimony compounds and ammonium nitrate. The purification of antimony with subsequent utilization of the ammonium salts is quite labor-intensive.

When using these materials for the production of

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Catalysts are also formed particles with a low mechanical strength, which makes the use of the catalyst difficult in fluidized bed.

The purpose of the present invention is to eliminate the mentioned disadvantages.

This task consisted in the development of such a to produce the oxygen compounds of antimony with metals, which makes it possible to produce the compounds mentioned in a few steps, to intensify the process, the ■ To reduce raw material losses, to avoid the formation of waste water and harmful gas development.

This object is achieved in that a process for the production of the oxygen compounds of antimony with metals by the oxidation of trivalent antimony to a pentavalent antimony and by the reaction of the latter with at least one of the metals, which is in the form of a salt, a hydroxide or a Oxides is used, is proposed in an aqueous medium and by subsequent drying and annealing, which is characterized in that the antimony trioxide to antimony pentoxide by means of hydrogen peroxide in an amount equal to or greater than the stoichiometric amount at temperatures between 40 and 100 ⁰ C is oxidized.

The use of hydrogen peroxide as an oxidizing agent makes it possible, compared to the processes in which nitric

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acid used as an oxidizing agent has a number of advantages to achieve. In the process according to the invention, the stage of precipitation of antimony and metal hydroxides, which are formed after the oxidation, as well as their subsequent washing off until a neutral reaction is produced, which leads to the formation of a larger amount of sewage containing high concentrations of antimony, which has a harmful effect on the environment and requires the use of complex and expensive cleaning procedures.

In addition, the formation of harmful gas emissions such as nitrogen oxides is completely excluded.

The consumption of hydrogen peroxide is determined by the stoichiometry the reaction of the oxidation of antimony trioxide to antimony pentoxide. It is recommended that in practice the Oxidation, to carry out of antimony in a small excess of hydrogen peroxide, in order to thereby reduce the influence of the To exclude factors not to be taken into account, v / eil the raw material may contain small additions, which the effect inhibit the reactor material, etc.

In the present process one can use hydrogen peroxide at a concentration of 33 to 5% . The particle size of the hydrated antimony pentoxide can be regulated by the amount of water, and by changing the temperature of the oxidation - the intensity of the process and the degree of crystallizability of the hydrated antimony pentoxide can be regulated. The

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preferred ratio between the solid and the liquid phase in the stage of oxidation of antimony trioxide, as well as in Mixing stage of hydrated antimony pentoxide and the metal compound is 1i4 each.

The preferred temperature of the processes is 80 ⁰ C.

The colloidal antimony pentoxide formed in the hydrated state serves as a stabilizer of the hydrogen peroxide, which leads to a reduction in the loss of hydrogen peroxide during the oxidation process, because it is an independent Decomposition of the hydrogen peroxide is prevented.

The mixing of a freshly prepared hydrated antimony pentoxide with metal compounds at temperatures between 40 and 100 ^° C. enables the reaction of the metal compound with the hydrated antimony pentoxide or the formation of solid solutions immediately in the mixing stage, which makes it possible to reduce the temperature of the annealing of the materials to increase the strength of the particles and to regulate the specific surface area over a wide range, which is of great importance in the manufacture of the catalysts.

The inventive method enables oxygen compounds of antimony with the following metals and elements manufacture: Pe, Sn, Bi, Ni, Co, V, Mo, W, Cr, Ce, Mh, Al, Ti,

TTT
Sb ^x , Cu, Ca, Ba, Mg, Fb, Nb, Ta, Te, P, B.

If the metal compound does not form a catalyst for the decomposition of hydrogen peroxide, it is recommended

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to reduce the number of steps when carrying out the process, the treatment of antimony pentoxide with hydrogen peroxide in the presence of the compounds Sn, Ti, La, Al, Mo, ¥ to be carried out.

In such an embodiment of the process, the stage of mixing the hydrated antimony pentoxide becomes Avoided with metal compounds because the formation of the oxygen compounds of antimony with metals at the same time in a reaction zone common to the reaction of oxidation of antimony trioxide takes place.

It is useful when carrying out the process for the preparation of the oxygen compounds of antimony with metals to use hydroxides of these metals as metal compounds. This makes it possible to completely eliminate the waste from production exclude increasing the yield of finished product up to 100? 6 and the introduction of undesirable mixtures to avoid in the final product.

It is recommended to use iron hydroxide for the production of the oxygen compounds of antimony and iron, which, converted to the corresponding oxides, is used in a weight ratio to antimony pentoxide of 1: 4 (Fe ₂ Q ^; Sb ₂ O ^ = 1: 4) will.

The use of iron hydroxide allows production waste to be eliminated completely exclude and produce material with a high mechanical strength.

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The oxygen compounds of antimony with iron are widely used in industry as catalysts oxidative ammonolysis of propylene in the manufacture of acrylonitrile. According to the proposed embodiment of the Process produced oxygen compound of antimony with iron, which contains 1 part by weight of Fe pO ^ per 4 parts by weight of SbpO, forms one of the most common catalysts for the above-mentioned oxidation processes. The inventive Process allows this catalyst to be prepared in a more convenient way compared to the known processes. -.

In the case where it is necessary in the antimony-iron catalyst The introduction of compounds of other metals as modifying additives can be done under the conditions of implementation realize the method according to the invention without increasing the number of technological stages, that the additives mentioned are introduced in the required amount at the same time as the iron compounds.

Since the known and currently applicable processes for the production of metal antimonates are mostly multistage, labor-intensive and ^{require temperatures of over 130O 0} C for their implementation, it is recommended that the hydrated antimony pentoxide with a metal compound in a corresponding stoichiometric ratio for the production of metal antimonates mix. The material produced is similar to the known process, preferably after the atomization

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process at temperatures between 120 and 200 ⁰ C dried.

It is recommended to carry out the glowing through the product at temperatures between 300 and 700 ^0C. A reduction in the temperature of the glow through compared to the known processes is achieved in that when the hydrated antimony pentoxide is mixed with a metal compound at temperatures between 40 and 100 ^° C., a chemical reaction or the formation of solid solutions takes place.

The method according to the invention has the following advantages: When using the method according to the invention, the The technological scheme is simplified because individual stages such as the precipitation of antimony and metal hydroxides by a base are made acidic solutions, filtration and washing off of the precipitated products produced can be eliminated.

The apparatus design of the process is simple.

By using hydrogen peroxide as an oxidizing agent, the pollution of the wastewater is reduced with antimony as well the harmful emissions into the atmosphere are completely prevented.

Carrying out the oxidation at elevated temperatures leads to a significant increase in the speed of the process of the process and allows the hydrated antimony pentoxide to be in the crystalline state as well as in the hydrogen ion form to obtain.

The production of the hydrated crystalline antimony in hydrogen ion form ensures already in the stage of the

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mixing of antimony with a metal compound results in the formation of an oxygen compound of antimony with metal, which allows in addition to significantly reduce the temperature of the annealing in comparison to the known processes. .

The hydrated antimony pentoxide can act independently as a cation exchanger in hydrogen form as well as in the chemical, metallurgical industry and in other "industries associated with various types of ion separations, particularly for extraction of alkali and alkaline earth metals from solutions with a very low metal content.

In that when carrying out the method according to the invention the number of stages of the process is reduced and that If washing is no longer necessary, the losses of raw materials are reduced and the yield of the end product is increased.

The method according to the invention makes it possible to use both metal antimonates as well as metal oxide antimony catalysts with a high mechanical strength, which is why the use this material enables the fluidized bed.

For example, the mechanical strength (airborne dust in% by weight 6 within 100 hours of work in a pipe with a linear air velocity of 10 cm / sec) in a catalyst produced by the process according to the invention is less than 0.3% t during-at the other known catalysts this value makes up 1.5 to 3, k%.

In the following, the invention will be explained with reference to the description of FIG

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"preferred embodiment of the method explained.

To prepare the oxygen compounds of antimony, for example with iron v / ground according to the invention in an enamelled reactor equipped with a stirrer 155 1 of demineralized water were placed and heated to a temperature of 80 ⁰ C (antimony catalyst iron). 83.5 kg of antimony trioxide and 90 liters of a 3O α-hydrogen peroxide are introduced with stirring, which corresponds to a molar ratio of 1: 3. The suspension is held within 0.5 to 1 "hour, and iron hydroxide is added with stirring in an amount of 23.3 kg (converted to Fe ₂ O- *), which corresponds to a ratio of Fe ₂ O ^ to Sb ₂ O ₁ - = 1: 4 corresponds.

The reaction mass is stirred and within 0.5 to 1 hour fed to a spray-drying at temperatures between 200-250 ⁰ C. The dry powder is collected in centrifugal separators, and from there fed into a rotary kiln, injdem it is kept at a temperature of 700 ⁰ C within 0.5-1 hours. The end product obtained has a special

Specific surface area of 47.6 m / g, mechanical strength for "the crushed grain fraction of 100-200 µm in the test in a chamber with a rotating impeller (3500 rpm) within 40 min - 90? 6.

The degree of conversion of propylene when using the invention Catalysts was 80.3 ^, the selectivity, based on acrylonitrile - 57.9%. The determination was carried out on a flow-through system in pseudo-liquefied catalyst

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exposure carried out.

In the following, the invention is explained by means of specific exemplary embodiments.

example 1

100 ml of water are poured into a reaction vessel and 50 g of SbpO are added with stirring. The resulting suspension is heated to a temperature of 40 ⁰ C. 50 ml of a 30% hydrogen peroxide solution are poured into the heated suspension. The mixture is kept stirring for 5 to 7 hours until the oxidation has ended. A previously prepared aqueous suspension containing 13> 8 g of FepO is added to the hot suspension (with stirring).

The mass produced is dried at a temperature of about 100 ^° C. within 3 hours and then in the air at a. Annealed to a temperature of 700 C within 4 hours. The product produced can be used as an iron-antimony catalyst. The yield is 100% of theory. The iron-antimony powder has a specific surface area

ρ ■

of 72 m / g. The mechanical abrasion resistance was for crushed Particles with a grain size of 100-200 am in the Testing in a chamber with a rotating impeller (3500 rpm) determined within 40 minutes. The yield of particles with a grain fraction of "^ 100 .mu.m after abrasion, what characterizing the magnitude of the relative strength, was 91 / S.

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Example 2

100 ml of water are poured into a reaction vessel and 50 g of antimony trioxide are added while stirring. The mixture is heated to a temperature of 90.degree. About 50 ml of a 30% H ₂ O _{2 are} introduced into the heated suspension. The mixture is kept at this temperature for one hour, and then 100 ml of a solution of Fe (NO,), which contains 13.8 g, converted to Fe ₂ O ^, is poured in in small portions with stirring. The resulting mixture is durchgeglüht at a temperature of 120-130 ⁰ C dried within 4 hours and in air at a temperature of 700 ⁰ C within 4 hours.

The product produced has 80% Sb ₂ Oc and 20% Fe ₂ O ₃ in its composition and can be used as a catalyst in the production of acrylonitrile by oxidizing ammonolysis of propylene. The manufactured product has

a specific surface area of 47.6 m / g, a mechanical one Strength for grain fractions of 100-200 µm when tested in a chamber with a rotating impeller (3500 rpm) within 40 min - from 90% up.

The performance of the catalyst, based on acrylonitrile, was 80.3%, the selectivity - 57.9%. The determination. Was on a flow-through circulation system carried out in a fluidized catalyst bed.

Example 3

50 g Sb ₂ O ₃ and 41.8 g SnSO ^ are mixed with 300 ml water

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mixed, and the prepared suspension is heated to a temperature of 9O ⁰ C. 60 ml of a 30% strength hydrogen peroxide solution are introduced into the heated suspension. The mixture is stirred at a temperature of 90 ^° C. until the oxidation has ended (0.5 to 1 hour). The suspension obtained is fed to spray drying or a drying cabinet and ^{dried at temperatures between 120 and 140 °} C. within 4 hours then fully annealed in air at a temperature of 700 ^° C. within 3-5 hours.

The product obtained contains 70.6% Sb ₂ O ₅ and 29.4% SnO ₂ and can be used as a catalyst for the oxidation of organic substances.

Example 4

A material is prepared which contains 93% SnO ₂ and 7% Sb ₂ O ₅ . For this purpose, 132.5 g SnSO ^ and 6.3 g of Sb ₂ Oc mixed with 500 ml of water, and the resulting suspension is treated with 100 ml of a 30% hydrogen peroxide solution at a temperature of 40 ⁰ C with stirring over 30 Minutes oxidized. The suspension is then heated to a temperature of 95 ^° C. and kept at this temperature for 0.5 hours.

The suspension prepared is dried at a temperature of 120-150 ⁰ C and then durchgeglüht at a temperature of 700 ⁰ C within 4 hours. The manufactured product can be used as a material for making resistors

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will.

example

50 g of Sbp (X are stirred with 100 ml of water, and the prepared. The suspension is heated to a temperature of 90.degree.

75 ml of a 30% hydrogen peroxide solution are poured into the heated suspension. The mixture is stirred at a temperature of about 90 ^° C. within one hour.

75 ml of a solution of Mn (NO-) p, which, converted to MnO, contains 12.1 g, are added to the thickened suspension with stirring. The mixture obtained is dried at a temperature of about 120 ^° C. over the course of 4 hours and calcined in air at a temperature of 300 ° C. over the course of 2 hours. A product is obtained which contains 82 # Sb ₂ O ₅ and 18 $ MhO; the product obtained can be used as a catalyst in the oxidation of organic substances.

Example 6

50 g of antimony trioxide are stirred with 100 ml of water, and the prepared suspension is heated to 95 ⁰ C. 40 ml of a 30% strength hydrogen peroxide solution are poured into the heated suspension, and the mixture is kept stirring for 0.5-1 hours. Barium hydroxide, which, converted to Ba, contains 23.5 g, is added to the suspension produced; the suspension is kept at this temperature with stirring for one hour. The mass obtained is dried at a temperature of 120 ⁰ C within 3 hours and at

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a temperature of 50O ⁰ C within 3 hours. The single-phase product produced consists of barium antimonate BaSbpOg. The parameters of the elementary cell are fol- low. gende: a = .4.63 S, c = 9.21 Sj they were determined by an X-ray structure analysis and correspond to an individual compound.

Example ^ J

Pour 100 ml of water into a reaction vessel and 50 g of antimony trioxide are added with stirring, after which the ' The mixture is heated to 95 ° C. 17-18 ml of a 33 μal hydrogen peroxide solution are added to the heated suspension, whereupon the suspension is kept at this temperature for a few hours. The mass obtained is aging at room temperature exposed until the yellow color appears.

. The product produced in this way is a semi-crystalline antimony tetroxide SbpO ^. SboOt- dar. After annealing within 3 hours at a temperature of 470 ⁰ C, the product to be treated is transformed into a crystalline product which has an orthorhombic unit cell with the following parameters: a = 4.804 S, b = 5.42 Å and c = 11.78 p.

Examples .8-11, 13, 14, 17, 18

Oxygen compounds or solid solutions are obtained under the conditions similar to those of Example 3 of antimony with metals, the technical data of which are given in the table below; the technical data were based on the results of an X-ray phase and a

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X-ray structure analysis determined.

Examples 12, 15, 16

Under the conditions which are similar to the conditions according to Example 4, oxygen compounds or are obtained solid solutions of antimony with metals, the technical data of which are given in the table below.

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Tabel

No.
the
at
games Starting
metal-coated
binding AgNO ₃ Structural forms 1
the oxygen
connection of
Antimony with
metal . structure
(Type) parameter
the elemen
tarzelle,
S. 10.23 Ί 2 Ba (OH) ₂
Ca (OH) ₂ 3 4th • 5 a = 5.29
C = 5.74
a = 5.23
c = 5.02 8th Mg (OH) ₂ AgSbO ₃ Ilmenite a = 4.63
c = 9.21 9
10 Al (OH) ₃ BaSb ₂ O ₆
CaSb ₂ O ₆ trigonal
(Rutile)
tetragonal -II- 11 Cr (NO ^ ₃ MgSb ₂ O ₆ - Il - -II- 12th Fb (NO ₃ ) ₂
Al (OH) ₃ AlSbO ₄ 10.38
a = 5.15
c = 5.17 13th La ₂ O ₃ CrSbO ₄ -Il - a = 5.30 14th
15th SnO ₂ Pb ₂ Sb ₂ O ₇
^IaAl O _f 5 ^Sb 1.5 ^P 6 Ilmenite
tetragonal Q = 5.18 16 Co (NO ₃ ) ₂ LaSnSbO ₆ - II _ a = 4.64
c = 9.25 Ni (N0 ₃ ) ₂ a = 4.63-
c = 9.18 17th CoSb ₂ O ₆ - II - 18th NiSb ₂ O ₆ - Il -

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Claims (3)

Claims 1. Process for the production of the oxygen compounds of antimony with metals by oxidation of trivalent antimony to a pentavalent antimony and reaction of the latter with at least one of the metals - which is used in the form of a salt, an oxide or a hydroxide, in an aqueous medium followed by drying and annealing the manufactured product, characterized in that the antimony trioxide to antimony pentoxide by means of ¥ asserstoffperoxyd in an amount that is equal to or exceeds the stoichiometric amount, this is oxidised at temperatures between 40 and 100 ⁰ C. 2. The method according to claim 1, characterized that iron hydroxide is used as the metal hydroxide, in a weight ratio to antimony pentoxide of 1: 4 each is used. 3. The method according to claim 1, characterized in that the through annealing of the product is carried out at temperatures between 300 and 700 ⁰ C. 509834/0497