CN101679190A - Separation of citric acid from gluconic acid in fermentation broth using a weakly or strongly basic anionic exchange resin adsorbent - Google Patents

Abstract

Citric acid is separated from a fermentation broth containing gluconic acid by using an adsorbent comprising a water-insoluble, macroreticular or gel, strongly or weakly basic anionic exchange resin possessing quaternary or tertiary amine functional groups, said a anionic exchange resin having a cross-linked acrylic or styrene resin matrix and a desorbent comprising water or dilute sulfuric acid.The pH of the feed is maintained below the first ionization constant (pKa1) of citric acid to maintain selectivity.

Description

Use separation of citric acid in weakly alkaline or the gluconic acid of strongly basic anion exchange resin sorbent material from fermented liquid

Invention field

[0001] technical field of the present invention be from comprise citric acid, organic acid for example the fermented liquid (fermentation broth) of gluconic acid or equisetic acid, carbohydrate, amino acid, protein and salt the solid bed adsorption of separation of citric acid separate.More particularly, the present invention relates to be used for the method from the gluconic acid separation of citric acid, this method has been used the sorbent material that comprises the particular polymers of selective adsorption citric acid from the fermenting mixture that contains citric acid and gluconic acid.

Background of invention

[0002] citric acid is used as the food souring agent, and is used in medicine, industry and the sanitising agent prescription.Popularization with liquid cleaning agent prescription increase of citric acid is to cause the major cause of the about 700,000,000 pounds of citric acids of annual in the world extensively preparation, and expectation will continue this situation in future.

[0003] by using molasses (molasses) and microorganism aspergillus niger (Aspergillus-Niger) dipping cultivation and fermentation process to prepare citric acid as raw material.In some applications, tunning or contain organic acid, for example gluconic acid or equisetic acid carbohydrate, amino acid, protein and salt and must be from fermented liquid isolating citric acid.

[0004] there is the historical technology of two kinds of uses to be used for from the fermented liquid separation of citric acid.US3, disclosed first method comprises and uses the calcium precipitation citric acid in 086,928.With the last citrate of lime of sulfuric acid acidation.In the second approach, with trilaurylamine (Tridodecylamine, n-Octanol and C ₁₀To C ₁₁The mixture of isoparaffin from fermented liquid, extract citric acid.From solvent phase, extract citric acid again in water with other heat.But these two kinds of technology are all complicated, expensive and they have all produced a certain amount of refuse that needs disposal in fact.

[0005] this patent documentation has been advised a kind of possible the third method that is used for from the fermented liquid separation of citric acid, it comprises that membrane filtration is to remove raw material or high molecular impurity and then pollutent to be adsorbed on based on carrying out the citric acid crystallization on the nonionic resin of polystyrene or polyacrylic resin and after citric acid in collection eliminating phase or the isoparaffin and the solution concentration, perhaps by using H after the citric acid of precipitation as calcium salt ₂SO ₄Acidifying, separation of C aSO ₄And contact with anionite with positively charged ion.EP 151,470 disclosed this methods also are a kind of suitable complexity and the tediously long method that is used for separation of citric acid.In contrast, present method makes in single step separation of citric acid and reclaim citric acid be called possibility in the method for simplifying very much.In brief, must adsorb citric acid and for example pass through strippant, the citric acid of water or diluted acid, sulfuric acid, hydrochloric acid, citric acid or phosphoric acid desorb purifying by the sorbent material selectivity.

Summary of the invention

[0006] the present invention relates to a kind of method, be used for being adsorbed on citric acid on alkaline, macroreticular or gel type, water-insoluble, as the to have tertiary amine functional group anionite-exchange resin or having weakly alkaline, macroreticular or gel type, water-insoluble, the anionite-exchange resin matrix that has tertiary amine functional group or pyridine functional groups from containing the organic acid fermented liquid that is selected from the group of forming by gluconic acid and equisetic acid or their mixture.Resinous substrates is acrylic acid or the like or styrenic, use divinyl benzene crosslinked.Reclaim citric acid by water under desorption condition or rare mineral acid, particularly desorb of sulfolysis vapor.The concentration of operable mineral acid is that about 0.01N arrives about 1.0N in the present invention, is preferably 0.1 to 0.2N.These resins cause comparing improved the separation with disclosed resinene in the early time.The stability of their passivation of impurity in increasing and be outstanding in the fractionation by adsorption citric acid at raw material.One aspect of the present invention is that from salt and carbohydrate separation of citric acid fully is only by adjusting and keeping the pH value of material solution to be lower than the first ionization constant (pKa of citric acid ₁) (3.13) acquisition.But the pH value in 0.5 to 2.5 scope is preferably and more preferably 1.5 to 2.2.Surprisingly gluconic acid separate with equisetic acid fabulous because the ionization constant of gluconic acid and equisetic acid is so near citric acid.

[0007] the invention still further relates to a kind of being used for from comprising the method for the raw mix separation of citric acid that contains gluconic acid or equisetic acid or the fermented liquid of the two, described method has been used water-insoluble, macroreticular or gelatinous strongly basic anion exchange resin with quaternary ammonium functional group, or have a weak base anion-exchange resin of tertiary amine or pyridine functional groups, described anionite-exchange resin has crosslinked acrylic acid or the like or styrene resin matrix, it may further comprise the steps: (a) remaining on the single direction flows passes the net flow body of described sorbent material tower, and this tower comprises that at least three stub areas with zone that operating function separately takes place therein and the tower by described connection are connected in series mutually so that the continuous connection in described zone to be provided; (b) keep adsorption zone in described tower, described zone is limited by the sorbent material between the raffinate output logistics of importing logistics and described regional downstream edge place at the raw material at described regional upstream edge place; (c) remain on the purifying zone that the upstream is close to described adsorption zone, described purifying zone is limited by the sorbent material between the raw material input logistics of exporting logistics and downstream edge place, described purifying zone at the extract at upstream edge place, described purifying zone; (d) remain on the desorbent zone that the upstream is close to described purifying zone, described desorbent zone limits by the sorbent material between the described extract output logistics of importing logistics and described regional downstream edge place at the strippant at described regional upstream edge place; (e) under adsorption conditions, make described raw mix enter described adsorption zone and comprise for example other not raffinate output logistics of absorbed component of gluconic acid, equisetic acid or their mixture and fermented liquid of organic acid so that realize taking out to the selective adsorption of described citric acid and from described adsorption zone by the described sorbent material in described adsorption zone; (f) under desorption condition, make desorbent material enter described desorbent zone so that in described desorbent zone, realize of the displacement of described citric acid from sorbent material; (g) take out the extract output logistics that comprises described citric acid and desorbent material from described desorbent zone; (h) make the described extract output of at least a portion flow to the extract separating device and under separation condition, separate the described desorbent material of at least a portion therein; And (i) raw material input logistics, raffinate output logistics, strippant input logistics and extract output logistics are advanced pass described sorbent material tower and pass described sorbent material and output logistics of preparation extract and raffinate output logistics to realize that the zone is switched.

[0008] the described raffinate logistics of at least a portion can be passed separating device under separation condition, therefore separates the described desorbent material of at least a portion has the desorbent material concentration of reduction with preparation raffinate product.In addition, the buffer area can remain on the upstream and be close to described desorbent zone, and described buffer area is defined as the sorbent material between the raffinate output logistics at the strippant input logistics at downstream edge place, described buffer area and upstream edge place, described buffer area.

[0009] other aspects of the present invention comprise the details of hereinafter disclosed raw mix, sorbent material, strippant and operational condition.

Summary of drawings

[0010] Fig. 1 is the graphic representation of the relative citric acid dissociative of different citric acid species concentration pH value, and it demonstrates moving by the citric acid dissociative trim point that changes citric acid, citrate and hydrionic concentration.

[0011] Fig. 2 is for using the graphic representation of quaternary ammonium functional group pulse test of separation of citric acid, the desorb of usefulness dilute sulphuric acid from the raw material of the gluconic acid that comprises 15% citric acid and 7% under 2.2 pH value in the example I in crosslinked acrylic resin matrix.

[0012] Fig. 3 uses quaternary ammonium functional group from separation of citric acid the raw material that comprises 20% citric acid and equisetic acid (below the limit of detection in analytical instrument) under 2.2 the pH value, the graphic representation of the pulse test of usefulness dilute sulphuric acid desorb in crosslinked acrylic resin matrix in the example II.

Detailed Description Of The Invention

[0013] beginning to locate to define the different terms that runs through whole specification to so that the clear of the operation of this method, purpose and advantage is useful.

[0014] " raw mix " is to comprise one or more extract components and one or more raffinate component mixtures by what method of the present invention was separated. " feed stream " vocabulary shows the raw mix logistics of passing for the adsorbent of the inventive method.

[0015] " extract components " is to adsorbent more compound or the type of compounds of selective absorption, and " raffinate component " is compound or type of compounds than non preference absorption. In this method, citric acid is extract components, and protein, amino acid, salt and carbohydrate are the raffinate components. The general expression of " desorbent material " word can the desorb extract components material. " strippant logistics " or " strippant input logistics " vocabulary shows that desorbent material is delivered to the logistics of adsorbent by it. " raffinate logistics " or " raffinate output logistics " expression raffinate component is by its logistics of removing from adsorbent. The composition of raffinate logistics can change to being essentially 100% the raffinate component from 100% desorbent material in essence. " extract flow " or " extract output logistics " word will represent that extract material by the desorbent material desorb is by its logistics of removing from adsorbent. Similarly, the composition of extract flow can change to being essentially 100% the extract components from 100% desorbent material in essence. Be delivered in the separation equipment from the extract flow of at least a portion of separation process and the raffinate logistics of preferred at least a portion, be typically fractionating column, wherein at least a portion desorbent material separates to prepare extract product and raffinate product. " extract product " and " raffinate product " expression comprises respectively the product that this method of the high extract components of concentration ratio extract flow and raffinate logistics and raffinate component obtains. Although might prepare highly purified citric acid product with the high rate of recovery by method of the present invention, it is evident that extract components never can adsorb by adsorbent fully. Similarly, the raffinate product is fully non-adsorbable or only has and be adsorbed on a small quantity agent absorption. Therefore, the raffinate component of different amounts in extract flow, can occur, similarly, the extract components of different amounts in the raffinate logistics, can occur. Then extract and raffinate logistics are further mutually distinguished and are formed raw mix with the ratio of the concentration of the concentration of extract components in the specific logistics and raffinate component. More particularly, citric acid will be minimum in the raffinate logistics with ratio than the concentration of the component of non preference absorption, and is secondly the highest and the highest in extract flow in raw mix. Similarly, the highest in the raffinate logistics than the component of non preference absorption and ratio than the concentration of the citric acid of selective absorption, secondly the highest in raw mix, and minimum in extract flow.

[0016] " the selective pore volume " of adsorbent is defined as the volume of the adsorbent of selective absorption extract components from raw mix. The adsorbent non preference that " the non-selective spatial volume " of adsorbent is keeps the volume from the extract components of raw mix. This volume comprises the cavity of the adsorbent that comprises non-adsorptivity site and the interstitial void space between the absorbent particles. Selective pore volume and non-selective spatial volume represents with volume usually and be very important for the adsorbent of specified rate determining to be delivered to the suitable flow velocity of fluid that is used for occuring valid function in the operating area. When adsorbent " entered " operating area (limit hereinafter and describe) of an embodiment that is used for the inventive method, its non-selective spatial volume and its selective pore volume were written into fluid in that zone. Non-selective spatial volume is used for determining to be delivered to same area is present in the fluid of the fluid in the non-selective spatial volume to the adsorbent displacement amount in countercurrent direction. To be delivered to the non-selective spatial volume speed of the sorbent material in this zone less if Fluid Flow in A is delivered to velocity ratio in the zone, and liquid is entrained in this zone only by adsorbent. Because this only carrying secretly is the fluid that is present in the non-selective spatial volume of adsorbent, it comprises the raw material components that non preference more keeps in most example. In some instances the selective pore volume of adsorbent can be from be enclosed in the fluid around the adsorbent a part of raffinate material of absorption because have competition for the adsorption site in the selective pore volume between extract material and the raffinate material in some instances. If a large amount of raffinate materials is enclosed in around the adsorbent with respect to the extract material, the raffinate material can have the competitiveness that is enough to be adsorbed agent absorption.

[0017] starting material of expection are the tunnings that comprises citric acid and gluconic acid and possible equisetic acid that is obtained by the dipping cultivation and fermentation of molasses by the microorganism aspergillus niger in the present invention.Tunning will have the component by following example:

Citric acid 10 quality %

Gluconic acid 7 quality %

Salt 6000ppm

Carbohydrate (sucrose) 1 quality %

Other (protein and amino acid) 2 quality %

Perhaps

Citric acid 20 quality %

Gluconic acid 1 quality %

Equisetic acid is lower than the limit of detection of analytical instrument

Salt 6000ppm

Carbohydrate (sucrose) 1 quality %

Other (protein and amino acid) 2 quality %

[0018] this salt is K, Na, Ca, Mg and Fe.Carbohydrate is the sugar that comprises glucose, wood sugar, seminose, DP2 and DP3 and high to 12 or the oligose of more unacknowledged sugar.The composition of material can and still be used for the present invention according to above variation to some extent.But fruit juice for example citrus fruits fruit juice is unacceptable or is not expection, because other material that is contained in wherein will adsorb rather than adsorb separately citric acid simultaneously.Johnson，J.Sci.Food?Agric.，Vol?33(3)pp?287-93。

[0019] as US4, to be discussed in 851,573 and US4,851,574, the separation of citric acid can be adjusted to first ionization constant that is lower than citric acid by the pH value with raw material and significant the reinforcement.First ionization constant (the pKa of citric acid ₁) be 3.13, Handbook of Chemistry ﹠amp; Physics, 53 ^RdEdition, 1972-3, CRC Press, therefore, the pH value of citric acid raw material should be lower than 3.13.As US4,851,573 and US4,851, illustrated in 574, for example, when the pH value of the citric acid solution of 40% concentration is 2.4 or when bigger, as the patent US4 that quotes, 851, shown in Fig. 3 A (example I) of 574, citric acid " penetrates " (desorb) in the circulation beginning with the salt and the carbohydrate that use, shows and all not absorption of citric acid.On the contrary, when the pH value is low to moderate 1.2, sees Fig. 3 B of the patent of quoting and be low to moderate 0.9 o'clock, see Fig. 3 C, observe " penetrating " of few gradually citric acid.Below explain it to be correct.

[0020] check the strong basic ion exchange resin that contains quaternary ammonium functional group of the present invention, quaternary amine has positive charge and can form ionic linkage with sulfate ion.The sulphate form of quaternary ammonium anion resin has weakly alkaline, and it conversely can be by the interaction absorption citric acid of acid-alkali.

Or

Wherein:

P=resin part

R=low alkyl group C1-3

The CA=citrate ion

Or hydrogen bond:

[0021] in addition, check the weak-base ion-exchange resin that contains tertiary amine and pyridine functional groups of the present invention, from the lone-pair electron of nitrogen-atoms can, for example, with tertiary amine

Or

And with the resin that contains pyridine functional groups

Wherein:

P=resin part

R=low alkyl group C1-3

The CA=citrate ion,

Directly or by sulfate ion and citric acid form hydrogen bond,

[0022] for the raw material of higher pH, will there be enough hydrogen ions to be used for forming hydrogen bond with amine nitrogen or sulfate ion, citric acid can not and will " penetrate " when round-robin begins with salt and carbohydrate by resin absorption.Can envision similar explanation to the resin that contains pyridine functional groups.

[0023] still, even according to this discovery early, from gluconic acid and or equisetic acid separation of citric acid also be wonderful because the first ionization constant (pKa of gluconic acid ₁) be 3.86 and the first ionization constant (pKa of equisetic acid ₁) be 2.8, the two is close with citric acid all.Do not expect the pH value that keeps raw material hang down cause from gluconic acid with or the separating of the citric acid of equisetic acid.

[0024] desorbent material that is used for multiple prior art adsorption separating method depends on these factors and changes, as the operation types of using.In the oscillating bed system, wherein the selective adsorption feed composition is removed from sorbent material by purge stream, strippant is selected not crucial and desorbent material contains hydrocarbon gas, methane for example, ethane etc., the perhaps gas of other types, for example nitrogen or hydrogen can use at the pressure of temperature that raises or reduction or under two kinds of conditions so that effectively clean the absorption feed composition from sorbent material.But usually basic under constant voltage and constant temperature operate continuously with the adsorption separating method that guarantees liquid phase in, desorbent material must be wise select to satisfy many standards.The first, to such an extent as to desorbent material should be replaced and itself do not had so strong adsorptivity from the extract components of the sorbent material with reasonable quality flow rate excessively stop extract components displacement sorbent material in the sorption cycle of back.With selectivity (hereinafter discussing in more detail) expression, with respect to the raffinate component, it is more selective as desorbent material that preferred adsorbent is compared to the raffinate component to all extract components.The second, desorbent material must be compatible with the specified raw material mixture with particular adsorbent.More particularly, they must not reduce or destroy with respect to the critical selectivity of raffinate component sorbent material for extract components.Desorbent material should be isolating material in the raw mix that is easy to from the process of being delivered in addition.The method extract product and the raffinate degree of purity of production that are separated to the small part desorbent material are removed and do not used to raffinate logistics and extract flow all with desorbent material in the sorbent material from mixture will not be desorbent material very high and that can not obtain to utilize again during the course.Therefore expect that any desorbent material that is used for present method will preferably have visibly different mean boiling point than the component in the raw mix, so that allow by separating at least a portion desorbent material in the feed composition of simple fractionation from extract and raffinate logistics, so permission utilizes desorbent material during the course again." obviously different " used herein speech will represent that the difference between mean boiling point should be about at least 5 ℃ between desorbent material and the raw mix.The boiling range of desorbent material can be more higher or lower than the raw mix, and is last, desorbent material also should be easy to obtain and the therefore rational material of cost.In the method for the preferred isothermal of the present invention, equipressure, liquid-phase operation, 0.01 to 1.0N dilute sulphuric acid is effective especially desorbent material.Similarly, other diluted mineral acid for example hydrochloric acid, nitric acid, phosphoric acid and water can be used as strippant, but is not very effective.

[0025] prior art some feature of also generally acknowledging sorbent material is high expectations for the successful operation of selective adsorption method.These features are no less importants to present method.These features comprise: (1) is for the loading capacity of the volume of some extract components of sorbent material of every volume; (2) with respect to raffinate component and the absorption of strippant material extraction thing components selection; And the extract components of (3) enough pieces is to sorbent material and the absorption and the desorption rate that leave sorbent material.For the extract components of absorption designated volume, that yes is necessary for the capacity of sorbent material, does not have this capacity, and sorbent material is otiose for fractionation by adsorption.In addition, big more for the adsorbent capacity of extract components, sorbent material is good more.The capacity that increases particular adsorbent makes the amount of sorbent material of the extract components that might reduce the raw mix that is included in specific rate of injection that need be used for separating concentration known.The minimizing of amount that need be used for the sorbent material of specific fractionation by adsorption has reduced the cost of sepn process.Importantly the life period in some commercial expectations keeps the good initial capacity of sorbent material in the sepn process practical application.Second necessary sorbent material is characterised in that the capacity of sorbent material separate raw materials component, in other words, compares with another kind of component, and sorbent material is for adsorption selectivity that a kind of component has (β).Relatively adsorptivity not only can be for a kind of feed composition to express with alternative contrast, can also be to express between any raw mix component and the desorbent material.The selectivity (β) that this specification is used is defined as under EQUILIBRIUM CONDITION, and the ratio of two kinds of components of absorption phase is with respect to the ratio of two kinds of identical components of not adsorbing phase.Adsorptivity is shown in following equation 1 relatively:

Equation 1

Wherein C and D are that two kinds of components in the raw material of representing with percent by volume and subscript A and U represent absorption and adsorbed state not respectively.When the raw material that is delivered to adsorption bed is being decided to be equilibrium conditions with changing after adsorbent bed contacts when forming.In other words, absorption not and absorption mutually between do not have the clean transmission of generating material.Wherein two kinds of components selection were near 1.0 o'clock, and sorbent material does not have preferred property for a kind of absorption of component with respect to another kind; They are each other all with approximately identical degree absorption (or not adsorbing).Be below or above 1.0 along with β becomes, with respect to another kind of component, sorbent material has preferred adsorptivity for a kind of component.When sorbent material relatively for component C during with respect to the selectivity of component D, β is greater than the 1.0 preferred absorption that show in sorbent material component C.β less than 1.0 show to component D preferably adsorb and stay be rich in component C not absorption phase and the absorption of being rich in component D mutually.To such an extent as to should having for all extract components, the ideal desorbent material equals about 1 or be slightly less than 1 all extract components of selectivity and can be used as a class and the extract components that the desorbent material that uses rational flow rate carries out desorb and can in follow-up adsorption step, replace desorbent material.When the adsorbents adsorb agent concerning the selectivity of extract components with respect to the raffinate component greater than 1 the time, separation and Extraction thing component is possible in theory from the raffinate component, preferred this selectivity is near 2.Similar relative volatility, selectivity are high more, easy more the separation.Higher selectivity allows to use more a spot of sorbent material.The 3rd important feature is the rate of exchange of the extract components of raw mix material, perhaps in other words, is the relative desorption speed of extract components.This feature directly relates to the amount that reclaims the desorbent material of extract components in the process of being not useable for from sorbent material; Therefore rate of exchange has reduced the amount of the desorbent material that need remove extract components and has allowed the reduction of the running cost of process faster.The speed of exchange is high more, and few more during the course desorbent material needs pumping to pass process and separate from extract flow being used for and utilize.

[0026] uses the different sorbent material of dynamic test equipment test with specified raw material mixture and desorbent material, so that measure loading capacity feature, selectivity and the rate of exchange of sorbent material.This equipment is formed by comprising 70cc volumetrical absorbent container straight shape or spiral tower, and described tower has the entrance and exit part in the opposite ends of container.This container is included in the Temperature-controlled appliance and in addition, has also used pressure control equipment to be used for operation vessel under the constant predetermined pressure.Quantitatively and qualitative analysis equipment refractometer for example, polariscope and chromatographic instrument can be attached to container outlet pipeline place and be used for detection by quantitative or qualitative one or more components of determining to leave the effluent logistics of absorbent container.The pulse test of using the common procedure of this equipment and back to carry out is used for determining selectivity and other data of different sorbent systems.With specific desorbent material by the desorbent material transmission is filled to balance by absorbent container with sorbent material.In time easily, the raw material or comprise in the two the time length of pulse at several minutes of raw material that comprises the specific extraction thing component of the tracer agent that dilutes of concentration known and raffinate component in whole strippants injects.The recovery strippant flows, and tracer agent and extract components or raffinate component (perhaps the two has) are as liquid-solid chromatography operation carrying out wash-out.Can in logistics, analyze effluent, perhaps, can regularly collect the effluent sample and analyze afterwards.

[0027] by test sorbent material deutero-information, performance can be with spatial volume, to the retention volume of extract or raffinate component, with respect to another kind of component to a kind of components selection, and extract components is by the speed statement of strippant desorb.The center at the peak that the retention volume of extract or raffinate component can be by extract or raffinate component and the peak of tracer agent component or the distance between some other known reference point characterize.It is explained in this wise, promptly with the peak-to-peak volume to represent with cubic centimetre apart from the strippant of representing that pumps into during this timed interval.With respect to the raffinate component, can characterize with the ratio of the distance between the center at the distance between the center of extract components peak and tracer agent peak (or other reference point) and corresponding raffinate component peaks and tracer agent peak for the selectivity (β) of extract components.The rate of exchange of extract components and strippant can characterize by the peak width under half intensity usually.Peak width is narrow more, and desorption rate is fast more.Distance between the center that desorption rate can also be by the tracer agent peak and extract components disappearance place of desorb just characterizes.This distance again be the volume of the strippant of pumping during this timed interval.

[0028] be actual sepn process for further evaluation sorbent systems likely and with such data conversion, need the actual test of carrying out best system in the liquid-solid contact device of continuous countercurrent.The common operating principle of this device had before been described and at US2, can find in 985,589.US3 has described the equipment of the particular experiment size that is used for these principles in 706,812.This equipment comprises adsorbent bed, has a plurality of turnover pipelines that are attached on the divider and end at the rotary distributor place in the bed.At given valve place, raw material and strippant pass through two pipeline introducings and raffinate and extract flow and take out by other two pipelines.Whole remaining turnover pipelines are inactive and when a scale was advanced in the position of distribution valve, a bed all can advance in all active positions.This simulated sorbent material wherein with the direction of liquid-flow adverse current on the condition that moves of physics.Other details for above-mentioned sorbent material testing apparatus and sorbent material evaluation technique can be at A.J.deRosset, R.W.Neuzil, D.J.Korous and D.H.Rosback are at AmericanChemical Society, Los Angeles, Calif., Mar.28-Apr.2, paper " the Separation of C that delivers on 1971 ₈Aromatics by Adsorption " in find.

[0029] sorbent material that is used for the inventive method will be included in strong basicity or the weak base anion-exchange resin that has quaternary ammonium, tertiary amine or pyridine functional groups in the crosslinked polymeric matrix, for example crosslinked substantially acrylic acid or the like or the styrene resin of divinyl.When the form with bead was prepared and have highly homogeneous effecting porosity of polymer blend membranes and show chemistry and physical stability, they were specially suitable.In the situation herein, this resin can be (to be Kunin and Hetherington as some nearest documents, A Progress Report on the Removal of Colloids From Waterby Macroreticular Ion Exchange Resins, be published in the paper on the International WaterConference, Pittsburg, PA, October 1969, Rohm ﹠amp; Haas Co. prints once more) in the word gelatinous (or " gel-type ") that uses or " macroreticular " shape.In adsorption technology, " macroreticular one speech refers to gel structure itself; its hole dimension is atomic size and swelling property that depend on gel ", and " it is bigger and be not the structure of the part of gel structure that macroreticular shape hole and true porosity refer to wherein the boring ratio atomic distance.Their size and dimension is not subjected to for example those conditions that cause osmotic pressure to change of remarkably influenced that envrionment conditions changes ", and the size of gel structure " depends on envrionment conditions " significantly.In " typical absorption ", " micropore and macropore one speech refer to respectively usually less than 20A with greater than those holes of 200A.The hole of diameter between 20A and 200A is called as transitional hole ".On the contrary, the author selects " macroreticular shape " speech to be applied in the new ion exchange resin that is used for the present invention, and it " has macroreticular and macroreticular shape pore structure.The former refers to the chain of swollen gel structure and the distance between the cross-linking set, and the latter refers to the hole of a part that is not actual chemical structure.In fact the macroreticular part of structure can be made up of micropore, macropore and transitional hole, and this depends on the distribution of sizes in hole " (quoting article page 1) from people such as Kunin.The large network structure sorbent material also has good wear resistance (different with the macroreticular shape resin of routine).Therefore in this application, all " macroreticular shapes " that relate to are all represented the sorbent material of the type with double porosity rate of Kunin described above and Hethesing definition." gel " and " gel-type " understood according to conventional.

[0030] sorbent material of for example just having described is made by Rohm and Haas Company, and sells with the trade name of " Amberlite ".Such Amberlite polymkeric substance that known valid is used by the present invention refers to sorbent material and the XE-275 (IRA-35) of Amberlite IRA400 and 900 series in the Rohm and Haas Company document, is described as those of " in all common solvents insoluble and have open architecture to realize macromolecular absorption and desorb not have the capacitance loss because of organic contamination " in IRA-68 sorbent material and the document.The AG1 that other are suitable for Bio Rad manufacturing, AG2, AGMP-I, the comparable resin that AG3-X4A and AG4-X4 resin and Dow Chemical Co. sell, for example Dowex 1,2,11, MSA-1, MSA-2,66 and according to US4, the Dow experiment resin of 031,038 and US4,098,867 preparation.The ion exchange resin that also usefully is called medium basic in the present invention, it is the mixture of strong basicity and weakly basic exchange resin.It in these the resin of commercially available acquisition: Bio-Rex 5 (Bio-Rad 1); AmberliteIRA-47 and Duolite A-340 are (all from Rohm﹠amp; Haas).For example, they to need in the situation than more weak or stronger than the alkalescence of the weakly base resin deacidite of the alkalescence of basic resin therein be useful.

[0031] these obtainable dissimilar polymer absorbants are slightly different on physical properties, for example pore volume percentage ratio, skeletal density and nominal particle size, and may be all the more so aspect surface-area, average pore diameter and moment of dipole.Preferred sorbent material will have the surface-area of 10-2000 square metre of every gram, and be preferably 100-1000m ²/ g.The specific nature of material listed above can find in company's document and technical manual, for example those in the following table 1.Can also obtain those of other kinds.

Table 1

[0032] application of the Amberlite polymer absorbant of advising in the document of Rohm and Haas Company comprises that slurry grinds the decolouring of bleaching effluent, the decolouring of dyestuff refuse and remove sterilant from waste effluent.Certainly do not hint in the literature that ours is wonderful about the discovery of Amberlite polymer absorbant in the validity of separation of citric acid from fermentation of Aspergillus niger liquid.

[0033] sorbent material can use with the form of the fixed bed of tight compression, and it alternately contacts with desorbent material with raw mix.In the simplest embodiment of the present invention, method only is in the situation of semicontinuity therein, uses sorbent material with the form of single static bed.In another embodiment, two or several static bed groups can be contact with suitable valve desorbent material can transmit form use by one or several other the fixed bed in this group so that the raw mix transmission is by one or several adsorbent bed.Flowing of raw mix and desorbent material can be passed strippant up or down.Can use any conventional equipment that is used for the contact of static bed fluid-solid.

[0034] still counter-flow moving bed or simulation moving-bed counter-current flow system has than the high a lot separation efficiency of fixed adsorbent bed system and is preferred therefore.In moving-bed or simulated moving bed process, absorption and desorb operation are carried out continuously, and this allows extract and the continuous preparation of raffinate logistics and the continuous use of raw material and desorb logistics.An embodiment preferred of the inventive method has been used the equipment that is called simulation moving-bed counter-current flow system in the prior art.US2 has described the order of operating principle and this current system in 985,589, and which is incorporated herein by reference.In this system, moving upward of the sorbent material that is included in the container simulated in the progressive motion of multiple liquid entry and exit point by absorbent container.The turnover pipeline only has four all to be active at any time; Raw material is imported logistics, is separated the suction port logistics, raffinate outlet logistics and extract inlet logistics turnover pipeline.Moving upward corresponding to the simulation of this solid adsorbent is the motion that occupies the liquid of sorbent material packed bed spatial volume.Therefore keeping counter current contact, liquid to be downward through absorbent container can provide by pump.Along with movable liquid entry and exit point moves through circulation, promptly from the top of container to the bottom, the container recycle pump moves through the zone of the different circulating rates of different needs.Can provide the program flow movement controller to control these flow rates.

[0035] movable liquid entry and exit point is divided into absorbent container the zone of separation effectively, and wherein each all has different functions.In this embodiment of the inventive method, the operating area of three separations that usually necessary is exists in proper order to realize present method, though can use the 4th optional zone in some cases.

[0036] adsorption zone, zone 1 are defined as the sorbent material between material inlet logistics and raffinate outlet logistics.In this zone, material contacts with sorbent material, the adsorption extract component, and take out the raffinate logistics.Because the feed stream from be delivered to this zone of usually flowing that passes zone 1 is to discharging this regional raffinate logistics, when outlet logistics campaign from the feed(raw material)inlet to the raffinate, mobile in this zone thought downstream.

[0037] be the purifying zone with respect to fluid flow in the zone 1 the upstream next-door neighbour, zone 2.The purifying zone is defined as the sorbent material between extract outlet logistics and the material inlet logistics.The elementary operation that takes place in zone 2 is that the sorbent material that passes through that carries out switches and enters the desorb that this zone is brought in the replacement of non-selective spatial volume of sorbent material of any raffinate material in the zone 2 and the selectivity pore volume at sorbent material or is adsorbed on the raffinate material of the lip-deep any absorption of absorbent particles.Purifying is sent into zone 2 realizations by the extract flow material that the upstream edge in zone 2 leaves zone 3 with a part, and extract outlet logistics is to realize the displacement of raffinate material.Material is being flowing on the downstream direction from extract flow to the material inlet logistics in 2 in the zone.

[0038] with respect to the zone 2 in fluid flow upstream immediate area 2 be desorbent zone or the zone 3.Desorbent zone is defined as the sorbent material between strippant inlet and the extract outlet logistics.The function of desorbent zone is to allow to enter in this regional desorbent material displacement circulation formerly in zone 1 previous period of contact with raw material and is adsorbed on extract components on the sorbent material.In the zone 3 fluidic flow basic with regional 1 and 2 in identical direction arranged.

[0039] can use optional buffer area in some cases, zone 4.This area limiting is the sorbent material between raffinate outlet logistics and the logistics of strippant inlet, if use, it is close in the upstream with respect to the fluid flow to zone 3.Zone 4 amounts that are used for preserving the strippant that is used for desorption procedure because the raffinate logistics that a part is removed 1 from the zone can be delivered in the zone 4 with displacement be present in this regional desorbent material outside this zone to desorbent zone.To such an extent as to zone 4 will comprise enough sorbent materials and can stop discharging area 1 and enter the raffinate material transfer that exists in 4 the raffinate logistics of zone and enter zone 3, pollute the extract flow of removing from zone 3 thus.Do not use therein in the situation in the 4th optional zone, be delivered to zone 4 raffinate logistics must carefully monitor raffinate material with convenient appropriate amount and be present in from regional 1 to regional 3 raffinate logistics the time from zone 1, can stop from zone 1 to the directly mobile of zone 3, to such an extent as to do not pollute extract outlet logistics.

[0040] input and output logistics is advanced and can be realized by using the manifold system by the circulation of the fixed bed of sorbent material, wherein the valve in manifold is operated in a sequential manner to realize the switching of input and output logistics, allows thus about the fluidic of solid adsorbent flowing in the mode of adverse current.Another kind of operator scheme can realize counter-current flow about the fluidic solid adsorbent for it, it comprises use rotation flaky valve, wherein input and output logistics contacts with pipeline with valve, advances on identical direction with raffinate output logistics with the input of pipeline raw material, extract output, strippant input by this valve and passes adsorbent bed.Manifold arrangement and flaky valve all are well known in the prior art, and the rotation flaky valve that particularly can be used for this operation can be at US3, find in 040,777 and US3,422,848.Aforementioned patent all discloses rotary-type connection valve, wherein from advancing of the different input and output logistics in fixing source can be without lifting an eyebrow realization.

[0041] in many cases, the zone of an operation will be than some other operating area comprise the sorbent material of much bigger amount.For example, in certain operations, compare with the sorbent material that needs are used to adsorb with the purifying zone, the buffer area can comprise more a spot of sorbent material.Can also see use can be simply from strippant the situation of desorb extracting substance, and at buffer area or adsorption zone or purifying is regional or the sorbent material that all needs in these zones is compared, in desorbent zone, need the sorbent material of relatively small amount.Owing to do not need sorbent material to be arranged in only tower, the use of multiple container or a series of towers is also included within the scope of the present invention.

[0042] use simultaneously and all input or output logistics not necessarily, and in fact, in many kinds of situations, one in the logistics can be cut off, and the inputing or outputing of other realization material.Can be used to realize that the equipment of the inventive method can also comprise a series of independent bed that links to each other by pipeline, be placed with on it and input or output joint, can be to its additional different inputing or outputing logistics and alternately and termly switches to effective successive operation.In some cases, the pipeline of connection can be connected with the transmission joint of the pipeline that does not enter or discharge by it as material in common operating period.

[0043] can be contemplated that at least a portion extract output logistics enters transmission in the separating device, wherein at least a portion desorbent material can separate the extract product that comprises the desorbent material that reduces concentration with preparation.Preferably, but to the operation of method of the present invention and nonessential be, at least a portion raffinate output logistics also can be delivered in the separating device, and wherein at least a portion desorbent material can separate desorb logistics that can utilize again during the course with preparation and the raffinate product that comprises the desorbent material that reduces concentration.This separating device is typically rectifying tower, and its design and operation are known in the isolation technique.

[0044] reference can be US2,985,589, incorporate the present invention here by reference into, and be used for the flow scheme of the movable bed adverse current method of further interpretive simulation.

[0045] though liquid and vapor phase operation all can be used in many adsorption separating methods, preferred liquid-gas phase operation for present method is because lower temperature requirement and because can obtaining than the productive rate with the higher extract product that gas phase operation obtained with liquid-phase operation.Adsorption conditions comprises about 20 ℃ of temperature that arrive in about 200 ℃ of scopes, and about 50 ℃ to about 90 ℃ is more preferably, and the pressure that about atmosphere is pressed onto in about 500psig (3450kPa gauge pressure) scope is preferred to guarantee the pressure of liquid phase.Desorption condition will comprise with adsorption conditions in employed identical temperature and pressure scope.

[0046] the unitary size that can be used for method of the present invention can be that pilot scale is (referring to for example incorporating US3 of the present invention by reference into, 706,812) to commercial size, and flow rate can per hour rise to several cc in several thousand gallons the scope from few in one hour.

[0047] following examples are used to illustrate the selectivity relation that makes method of the present invention become possible.These embodiment do not wish to limit the scope of claim.

Embodiment 1

[0048] in the present embodiment, with macropore, have quaternary ammonium functional group and with the strongly basic anion exchange adsorbing substance of the crosslinked acrylic resin matrix of Vinylstyrene matrix, IRA-958, carrying out pulse test determines at other components (DP1, DP2, the DP3 of 2.2 times sorbent materials of pH from the fermenting mixture of gluconic acid and carbohydrate, comprise glucose, wood sugar, pectinose and raffinose) and the ion of salt, comprise Na ⁺, K ⁺, Mg ⁺⁺, Ca ⁺⁺, Fe ⁺⁺⁺, Cl ^-, SO ₄ ⁼, PO ₄ ^≡And NO ₃ ^-, the ability of separation of citric acid in amino acid and the protein.P is the vinylformic acid with divinyl benzene crosslinked.This test is carried out under 60 ℃ temperature.Sulphuric acid soln desorb citric acid with 0.1N.The fermentation raw material mixture has following composition:

Raw material is formed	Mass percent
		Citric acid	??15.13
Gluconic acid	??7.29
		Salt (Na +，K +，Ca ++，Mg ++，Fe +++)	??1.5
Carbohydrate (sucrose)	Unknown
		Other materials (Cl -，SO 4 ＝，PO 4 ≡，NO 3 -)	??1.12
Amino acid and protein	??0.05
		Water	??75.0

[0049] use pulse test equipment and previously described process to obtain retention volume and separation factor.Especially, the operational testing sorbent material that is used for pulse test of order below the use in the straight shape post of 70cc.Desorbent material moves upward by comprising the post of sorbent material continuously with about 1.0 nominal liquid hourly space velocity (LHSV).The volume that is full of the strippant that the exsiccant post of filling needs by observation is determined spatial volume.Stop to flow of desorbent material in time easily, and be injected in post by sample loop the sample of the raw mix of 5cc and recover flowing of desorbent material.The sample of effluent is collected in the automatic sample collector automatically and is used for the analysis of salt and citric acid later on by stratographic analysis.Extract and raffinate component and the not separated analysis that is used for other feed composition for example are included in carbohydrate wherein, protein etc.The peak concentration of research raw mix component from the analysis of these samples.The retention volume of citric acid is calculated to the distance of the intermediate point at the peak of citric acid by measuring from the intermediate point of conduct with reference to the net retention volume at the peak of the salt of selecting.Separation factor β is calculated by the ratio of the retention volume of two kinds of compounds.The result of pulse test is as follows:

[0050] result also is presented among Fig. 2, wherein is clear that, in the method, citric acid is separated from gluconic acid and other fermented liquid component satisfactorily.

Embodiment 2

[0051] adopt similarly to Example 1 macroporosity, strongly basic anion exchange adsorbing substance IRA-958 and identical condition to carry out another pulse test, except the raw material biased sample that 10cc is replaced 5cc is injected in the post by sample loop.In addition, in this embodiment, also contain equisetic acid in the fermenting mixture.

Raw material is formed	Mass percent
		Citric acid	??20
Equisetic acid	Be lower than the limit of detection of analytical instrument
		Salt (K +，Na +，Ca ++，Mg ++，Fe +++)	??3.34
Carbohydrate (sugar)	Unknown
		Other materials (Cl -，SO 4 ＝，PO 4 ≡，NO3 -, amino acid and protein)	??1
Water	??75.66

[0052] analysis of raw material do not cause equisetic acid amount quantitatively, this is because this amount is lower than the limit of detection of analytical instrument.Use previously described pulse test equipment and flow process to obtain retention volume and separation factor.Especially, the sequential operation test sorbent material that in the straight shape post of 70cc, is used for pulse test below the use.Desorbent material moves upward by comprising the post of sorbent material continuously with about 1.0 nominal liquid hourly space velocity (LHSV).The volume that is full of the strippant that the exsiccant post of filling needs by observation is determined spatial volume.Stop to flow of desorbent material in time easily, and be injected in post by sample loop the sample of the raw mix of 10cc and recover flowing of desorbent material.The sample of effluent is collected in the automatic sample collector automatically and is used for the analysis of salt and citric acid later on by stratographic analysis.Extract and raffinate component and the not separated analysis that is used for other feed composition for example are included in carbohydrate wherein, protein etc.The peak concentration of research raw mix component from the analysis of these samples.The retention volume of citric acid is calculated to the distance of the intermediate point at the peak of citric acid by measuring from the intermediate point of conduct with reference to the net retention volume at the peak of the salt of selecting.Separation factor β is calculated by the ratio of the retention volume of two kinds of compounds.The result of pulse test is as follows.

[0053] this as a result liquid be presented among Fig. 3, be clear that wherein in the method, citric acid is gratifying to be separated from gluconic acid, equisetic acid and other fermented liquid components.

Claims (15)

1. the method for a fractionation by adsorption, it comprises makes the fermented liquid that comprises citric acid and gluconic acid at least contact with the water-insoluble basic anion exchange resin, described resin is selected from by having quaternary ammonium functional group and having the strongly basic anion exchange resin of crosslinked copolymerization vinylbenzene or acrylic resin matrix and have tertiary amine or pyridine functional groups and have crosslinked vinylformic acid or group that the weak base anion-exchange resin of styrene resin matrix is formed, wherein under the adsorption conditions of selecting with the described citric acid of selective adsorption, the water not form of capacitive basic anion exchange resin is selected from the group of being made up of sulphate form and amine-format, and described adsorption conditions comprises the first ionization constant (pKa that is lower than citric acid ₁) the pH value, and under desorption condition, with the strippant desorb citric acid that comprises water or diluted mineral acid.

2. the method for claim 1, it further comprises the recovery citric acid.

3. the method for claim 1, it is further characterized in that described absorption and desorption condition are included in 20 to 200 ℃ of temperature and pressure in barometric point and 500psig (3450kPa gauge pressure) scope in the scope.

4. the method for claim 1, it is further characterized in that described desorb realizes with dilute sulphuric acid in liquid phase.

5. the method for claim 1, it is further characterized in that described strongly basic anion exchange resin has quaternary ammonium functional group and described matrix is crosslinked acrylic resin.

6. the method for claim 1, it is further characterized in that described weak base anion-exchange resin has pyridine functional groups and described matrix is crosslinked polystyrene resin.

7. the method for claim 1, it is further characterized in that described weak base anion-exchange resin has tertiary amine functional group and described matrix is acrylic resin.

8. the method for claim 1, it is further characterized in that described anionite-exchange resin has 10m at least ²The surface-area of/g.

9. the process of claim 1 wherein that described fermented liquid comprises citric acid, gluconic acid, carbohydrate and salt.

10. the process of claim 1 wherein that described anionite-exchange resin is the macroreticular shape.

11. the process of claim 1 wherein that described anionite-exchange resin is gelatinous.

12. the process of claim 1 wherein that contact and desorb further comprise:

(a) remain on the single direction net flow body of the tower that passes described suction resin of flowing, this tower comprises that at least three stub areas with zone that operating function separately takes place therein and the tower by described connection are connected in series mutually so that the continuous connection in described zone to be provided;

(b) keep adsorption zone in described tower, described zone is limited by the resin between the raffinate output logistics of importing logistics and described regional downstream edge place at the raw material at described regional upstream edge place;

(c) remain on the purifying zone that the upstream is close to described adsorption zone, described purifying zone is limited by the resin between the raw material input logistics of exporting logistics and downstream edge place, described purifying zone at the extract at upstream edge place, described purifying zone;

(d) remain on the desorbent zone that the upstream is close to described purifying zone, described desorbent zone limits by the resin between the described extract output logistics of importing logistics and described regional downstream edge place at the strippant at described regional upstream edge place;

(e) under adsorption conditions, make described fermented liquid enter described adsorption zone so that realize that by the described resin in described adsorption zone taking out the raffinate that comprises gluconic acid at least to the selective adsorption of described citric acid and from described adsorption zone exports logistics;

(f) under desorption condition, make the desorbent material of the mineral acid that comprises water or dilution enter described desorbent zone so that in described desorbent zone, realize of the displacement of described citric acid from resin;

(g) take out the extract output logistics that comprises described citric acid and desorbent material from described desorbent zone;

(h) make the described extract output of at least a portion flow to the extract separating device and under separation condition, separate the described desorbent material of at least a portion therein; And

(i) tower that raw material input logistics, raffinate output logistics, strippant input logistics and extract output logistics is advanced pass described resin passes described resin and output logistics of preparation extract and raffinate output logistics to realize that the zone is switched.

13. the method for claim 12, it further comprises makes the described raffinate output of at least a portion flow to the raffinate separating device and separate the described desorbent material of at least a portion has the desorbent material concentration of reduction with preparation the step of raffinate product under separation condition.

14. the method for claim 12, it further comprises makes the buffer area remain on the step that the upstream is close to described desorbent zone, and described buffer area is defined as the resin between the strippant input logistics at downstream edge place, described buffer area and the raffinate output logistics at upstream edge place, described buffer area.

15. the method for claim 12, wherein said desorbent material are the sulfuric acid in 0.01N arrives the 1.0N concentration range.

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