Process for separating xylose mother liquor by using chromatography

Abstract

The invention belongs to the technical field of purification of carbohydrate derivatives, and particularly relates to a process for separating xylose mother liquor by utilizing chromatography. The process comprises the following steps: S1, preparing phenylboronic acid modified resin; s2, filling a chromatographic column with the phenylboronic acid modified resin to prepare a modified resin chromatographic column; s3, installing a modified resin chromatographic column in the simulated moving bed chromatographic system, and separating the xylose mother liquor to obtain a fast component, an intermediate component and a slow component; and S4, respectively concentrating the intermediate component and the slow component to obtain an intermediate component concentrated solution and a slow component concentrated solution. According to the invention, the existing resin is modified, and amido bonds are used as bridging grafting phenylboronic acid groups, so that the existing resin has good anti-pollution and regeneration capabilities; the method is used for purifying xylose mother liquor, and the separation efficiency of xylose and arabinose is further improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of saccharide derivative purification, and particularly relates to a process for separating xylose mother liquor by chromatography. BACKGROUND

[0002] Xylose mother liquor refers to dark brown viscous liquid remaining after centrifugation of xylose crystals, which can be divided into corn cob xylose crystal mother liquor and hemicellulose xylose crystal mother liquor. The main components are xylose and arabinose, and also include other monosaccharides such as glucose, galactose and mannose, organic acids, inorganic salts, pigments and colloidal suspensions. When the xylose mother liquor is purified, chromatography separation is often used to improve the purity of high-value components such as residual xylose and arabinose, and then the purified material is mixed with the main material for reproduction. At present, simulated moving bed chromatography (SMB for short) is often used for chromatography separation.

[0003] However, with the increase of the content of galactose, mannose and other impurities in the xylose mother liquor, the difficulty of chromatography separation is further increased, and the purity of xylose and arabinose in the purified material is low, and the recovery rate is low. The traditional ion resin used has the problems of easy blockage of the chromatographic column by pigments, difficulty in regeneration, and high cost due to the use of a large amount of eluent.

[0004] Chinese patent CN104661718A discloses a method for separating xylose from a solution containing xylose plants using a chromatography separation system, which includes one or more weakly basic anion exchange resins and optionally one or more other resins selected from strongly acidic cation exchange resins and weakly acidic cation exchange resins, and recovering at least one fraction rich in xylose. The weakly basic anion exchange resin is selected from acrylic resins, polystyrene resins, anion exchange resins based on epichlorohydrin, amine products of phenol or formaldehyde resins, aliphatic amines and ammonia condensation resins.

[0005] The anion resin in the patent separates impurities by anion exchange and is suitable for the separation of organic acids such as xylose and xylonate and other monosaccharides such as rhamnose. Since xylose and arabinose are structural isomers and both are neutral five-ring carbon sugars with high structural similarity, they are difficult to separate. The solution containing xylose in the patent is limited to the case where the arabinose content is low. If the patent is used for xylose mother liquor whose main components are xylose and arabinose, the economic efficiency and separation efficiency in industrial production cannot be verified when arabinose is separated.

[0006] Chinese patent CN102850408A discloses a method for preparing xylose and arabinose using simulated moving chromatography. The method uses xylose mother liquor as raw material, and the specific steps are as follows: a, simulated moving bed separation; b, purification of component A; c, filtration; d, concentration; e, crystallization. In the separation of simulated moving chromatography, the adsorbent is a macroporous adsorption resin, and the macroporous adsorption resin is ZGSPC106Ca2 + UBK530Na + UBK530Ca 2+ 99Ca 2+ -310 or CM155Ca 2+ One of the patent used macroporous adsorption resin is a traditional cation exchange resin, because the xylose mother liquor contains organic acid, inorganic salt and pigment; long-term operation will cause the resin to be blocked, and the patent has no pretreatment measures for deacidification, desalination and decolorization or resin regeneration measures, and the traditional cation exchange resin is not improved. SUMMARY

[0007] The purpose of the present application is to provide a process for separating xylose mother liquor by chromatography, and to improve the separation efficiency of xylose and arabinose by modifying the existing resin to prepare a phenylboronic acid modified resin with good anti-pollution and regeneration capacity.

[0008] To achieve the above purpose, the technical scheme adopted by the present application is: The process for separating xylose mother liquor by chromatography comprises the following steps: S1, preparing a phenylboronic acid modified resin; S2, filling the phenylboronic acid modified resin into a chromatographic column to prepare a modified resin chromatographic column; S3, installing the modified resin chromatographic column in a simulated moving bed chromatography system, and separating fast components, intermediate components and slow components from the xylose mother liquor; S4, concentrating the intermediate components and slow components respectively to obtain intermediate component concentrate and slow component concentrate.

[0009] Among them: The preparation process of the phenylboronic acid modified resin comprises the following steps: (1) blending styrene-divinylbenzene copolymer resin, chloromethylation reagent and organic solvent A for swelling, then adding catalyst for chloromethylation, and after chloromethylation is completed, obtaining chloromethylated resin through purification; (2) preparing mixed solvent A for standby, blending chloromethylated resin and mixed solvent A for swelling, then adding amination reagent for amination, and after amination is completed, obtaining aminated resin through purification; (3) preparing mixed solvent B for standby, blending 4-carboxyphenylboronic acid, carboxyl activating agent, amide promoting reagent and mixed solvent B for activation to obtain an activation liquid; adding the aminated resin into the activation liquid for modification; (4) after modification is completed, blending the aminated resin and hydrophobic coupling agent with organic solvent B, and keeping warm to obtain the phenylboronic acid modified resin.

[0010] The step (1) is characterized in that the styrene-divinylbenzene copolymer resin is a sodium ion type styrene-divinylbenzene copolymer resin (or simply referred to as Na + The step (1) is characterized in that the styrene-divinylbenzene copolymer resin is a sodium ion type styrene-divinylbenzene copolymer resin (or simply referred to as Na

[0011] The step (1) is characterized in that the stirring rate of swelling is 60-120 rpm, the swelling temperature is 25-35℃, and the swelling time is 30-35 min; the stirring rate of chloromethylation is 80-105 rpm, the chloromethylation temperature is 50-60℃, and the chloromethylation time is 1.5-2.5 h. The purification includes filtering, soaking and drying, and the soaking is performed by using toluene for 3 times, 8 min each time.

[0012] The step (2) is characterized in that the mixed solvent A is prepared according to the volume ratio of water:ethanol=1:(2.8-4.5), the amination reagent is ethylenediamine, and the addition amount ratio of the chloromethylated resin, the amination reagent and the mixed solvent A is 1000:(400-530):(4-4.5), wherein the chloromethylated resin and the amination reagent are measured in g, and the mixed solvent A is measured in L.

[0013] The step (2) is characterized in that the stirring rate of swelling is 30-60 rpm, the swelling temperature is 25-35℃, and the swelling time is 30-35 min; the amination temperature is 60-80℃, and the amination time is 1-1.5 h. The purification includes filtering, soaking and drying, and the soaking is performed by using ethanol for 3 times, 8 min each time.

[0014] The step (3) is characterized in that the mixed solvent B is prepared according to the volume ratio of toluene:N,N-dimethylformamide=1:(1.2-1.5), the carboxyl activation agent is N,N'-dicyclohexyl carbodiimide, and the amidation promoting reagent is N-hydroxysuccinimide; the addition amount ratio of the aminated resin, 4-carboxyphenylboronic acid, the carboxyl activation agent, the amidation promoting reagent and the mixed solvent B is 1000:(800-1000):(120-150):(80-120):(8.5-10.5), wherein the aminated resin, 4-carboxyphenylboronic acid, the carboxyl activation agent and the amidation promoting reagent are measured in g, and the mixed solvent B is measured in L; the activation temperature is 30-35℃, and the activation time is 15-30 min; the modification temperature is 40-45℃, and the modification time is 2-2.5 h.

[0015] In the step (4), the hydrophobic coupling agent is perfluorodecyltriethoxysilane, the organic solvent B is anhydrous ethanol; the adding amount ratio of the aminated resin, the hydrophobic coupling agent and the organic solvent B is 1000:(150-260):(5.5-6.5); the temperature of heat preservation is 42-45 DEG C, and the time of heat preservation is 25-45 min.

[0016] The simulated moving bed chromatography system comprises five main materials and six modified resin chromatography columns; the five main materials are composed of fast components, intermediate components, slow components, eluent and xylose mother liquor; and the six chromatography columns comprise a first chromatography column, a second chromatography column, a third chromatography column, a fourth chromatography column, a fifth chromatography column and a sixth chromatography column.

[0017] The column temperature of the modified resin chromatography column is 60-65 DEG C, and the column pressure drop is 1.1-1.5 MPa; the eluent is a sodium carbonate-sodium bicarbonate buffer solution with pH=9.5-10.5, the feeding flow rate of the eluent is 95-115 mL / min, and the feeding rate of the xylose mother liquor is 25-35 mL / min.

[0018] By utilizing the adsorption characteristics of phenylboronic acid in an alkaline environment, the sodium carbonate-sodium bicarbonate buffer solution is introduced to provide an alkaline environment, so that the coordination force difference between phenylboronic acid and arabinose and other xylose and monosaccharides is effectively separated.

[0019] The simulated moving bed chromatography method is to simulate the countercurrent flow of the fixed phase by connecting multiple columns in series and periodically switching the inlet of the mobile phase.

[0020] The elution sequence of the phenylboronic acid modified resin is in turn: glucose, galactose, mannose, arabinose and xylose.

[0021] The beneficial effects of the present application are as follows: (1) The electrophilic carbon (C=N) in the N,N'-dicyclohexyl carbodiimide molecule can attack the oxygen atom of the carboxylic acid to form a highly active intermediate (such as O-acyl isourea intermediate, R-COO-C=N-R'), which has a greater reaction activity than the carboxylic acid itself; the N-hydroxy succinimide promotes the reaction of the amino group with the highly active intermediate, and finally forms an amide bond, reduces the retention of the highly active intermediate, and reduces the generation of side reactions.

[0022] The amide bond is used as a bridge to graft the phenylboronic acid group to the Na + On the one hand, the amide bond exhibits excellent hydrolysis stability in an acid-base environment and at high temperature, ensuring that the Na +The S-DVB resin can maintain the benzene boronic acid structure integrity in multiple cycles of regeneration. In addition, the carbonyl and amino in the amide bond can form additional hydrogen bonds with the hydroxyl of the sugar, which cooperates with the pH responsiveness of the benzene boronic acid to further improve the Na + The S-DVB resin has a high adsorption capacity.

[0023] (2) The xylose and Na + The chelation ability of the S-DVB resin is weaker than that of arabinose. In the present application, the benzene boronic acid group is grafted as a pH-responsive switch. In addition to the pH-responsive effect, the benzene boronic acid can also recognize the conformational differences of xylose and arabinose, which cooperates with the Na + The S-DVB resin specifically adsorbs xylose or arabinose, further enlarges the adsorption force difference of xylose and arabinose on the resin, promotes the separation of xylose and arabinose, and further reduces the reverse mixing phenomenon. As a pH-responsive site, the benzene boronic acid root (-B(OH)3 - ) preferentially coordinates with the cis dihydroxyl group of arabinose (C2 / C3 hydroxyl group in cis) to form a stable five-membered ring structure; and has weak binding force with the trans hydroxyl group of xylose (C2 / C3 hydroxyl group in trans). At the same time, the benzene boronic acid root further forms steric hindrance after coordinating with the hydroxyl group of arabinose, which expels the xylose molecules and pigment macromolecules, weakens the hydrogen bond interaction between arabinose and xylose, facilitates elution, reduces the amount of eluent, and improves the production efficiency. At the same time, the fluorocarbon chain of perfluorodecyltriethoxysilane (PFDTS) forms a super-hydrophobic interface, which on the one hand prevents the re-adsorption of the detached pigment macromolecules, cooperates with the coordination of benzene boronic acid, and together promotes the stripping of the pigment macromolecules, solving the problem that the chromatographic column is easily blocked by the pigment, making regeneration difficult. On the other hand, it further improves the elution capacity of weakly bound xylose, reduces the amount of eluent and the reverse mixing phenomenon, and effectively improves the product purity and production efficiency of the intermediate component (containing xylose) and the slow component (containing arabinose). BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Structure diagram of a simulated moving bed chromatographic separation system after installing a modified resin chromatographic column; Among them: A, fast component; B, intermediate component; C, slow component; D, eluent; E, xylose mother liquor; 1, first chromatographic column; 2, second chromatographic column; 3, third chromatographic column; 4, fourth chromatographic column; 5, fifth chromatographic column; 6, sixth chromatographic column. DETAILED DESCRIPTION

[0025] The present application will be specifically described and explained in conjunction with the following examples.

[0026] In the examples and comparative examples, the raw materials and equipment used were all commercially available products. Some of the raw material manufacturers are as follows: Na+ type S-DVB resin was provided by Langfang Nanda Resin Co., Ltd.; xylose mother liquor, which mainly includes xylose, arabinose and other monosaccharides (galactose, mannose and glucose), was provided by Henan Yuxin Sugar Alcohol Co., Ltd.

[0027] Some equipment models are as follows: High Performance Liquid Chromatograph, model Agilent 1260, provided by Agilent Technologies.

[0028] Example 1 1. Preparation of phenylboronic acid modified resin (1) Take 1000g of Na + Type S-DVB resin and 1000g of chloromethyl octyl ether were added to a reaction vessel, followed by the addition of 9.5L of toluene. The mixture was stirred and allowed to swell for 32 minutes at 100 rpm and 30°C. After swelling was complete, 80g of anhydrous zinc chloride was added, and the mixture was reacted for 2 hours at 80 rpm and 55°C. After the reaction was complete, the mixture was filtered. The mixture was then washed three times in toluene for 8 minutes each time. Finally, it was dried until there was no change in weight to obtain the chloromethylated resin.

[0029] (2) Prepare mixed solvent A according to the volume ratio of water:ethanol = 1:3; put 1000g of chloromethylated resin into another reaction vessel, add 4.2L of mixed solvent A, purge with nitrogen, start stirring, and swell at 50rpm and 30℃ for 34min; after swelling is complete, add 430g of ethylenediamine, control the vessel temperature at 70℃, react for 1.2h, and filter after the reaction is complete; then wash in ethanol 3 times, 8min each time; finally dry until there is no change in weight to obtain amination resin.

[0030] (3) Prepare mixed solvent B according to the volume ratio of toluene:N,N-dimethylformamide = 1:1.3 for later use; mix 950g of 4-carboxyphenylboronic acid with 9.5L of mixed solvent B, add 135g of N,N'-dicyclohexylcarbodiimide and 105g of N-hydroxysuccinimide, and activate at 33℃ for 25min to obtain an activated solution. Add 1000g of amination resin to the activated solution and modify at 43℃ for 2.2h.

[0031] (4) After modification, the resin was taken out and added together with 220g of perfluorodecyltriethoxysilane into 5.8L of anhydrous ethanol. The mixture was kept at 43℃ for 40min. After filtration, it was washed in 0.8mol / L sodium chloride solution and dried until the weight changed, thus obtaining the phenylboronic acid modified resin.

[0032] 2. Preparation of modified resin chromatography column The phenylboronic acid modified resin prepared in Example 1 was mixed with deionized water at a weight ratio of 1:4 to form a homogeneous slurry. The slurry was centrifuged and degassed under vacuum for 10 min. A column packing pump was connected to the bottom of the column shell and the pump was turned on to circulate the slurry at a constant flow rate of 3 mL / min for 5 min. A slurry pump was connected to the top of the column shell and the slurry was added to the column shell at a rate of 5 mL / min. A clear sedimentation interface was observed. After the slurry was added, deionized water was pumped in at 8 mL / min and 2.6 MPa for 30 min. Finally, the top sieve plate was sealed, the column head seal was installed, and the column bed height was marked to obtain a 50 mm × 600 mm modified resin chromatographic column (column inner diameter of 50 mm and column length of 600 mm), which was labeled as Sample 1.

[0033] 3. Single-column evaluation test The phenylboronic acid modified resin obtained in Example 1 was used to prepare a test sample with a size of 7.8 mm × 150 mm according to the modified resin chromatographic column preparation method. The xylose mother liquor was filtered through a filter membrane to remove particulate impurities, and then degassed before use.

[0034] Turn on the high-performance liquid chromatograph (HPLC), preheat for 30 min, calibrate, and under the conditions of column temperature 60℃, column pressure 0.3MPa, and mobile phase flow rate 1.8mL / min, introduce a sodium carbonate-sodium bicarbonate buffer solution with a mobile phase pH of 9.5. Inject 10mL of xylose stock solution. The resolution R between xylose and galactose was measured. S The value is 0.462, which fully meets the requirements for separating xylose and galactose.

[0035] 4. Chromatographic separation A modified resin column was installed in a simulated moving bed chromatography (SMB) system, an existing process facility provided by Shandong Zhaoguang Chromatography Separation Technology Co., Ltd.; Figure 1 As shown, this simulated moving bed chromatography system includes five main materials and six modified resin columns. Eluent D (sodium carbonate-sodium bicarbonate buffer) is connected to the inlet of column 6; xylose mother liquor E is connected to the inlet of column 3; fast component A (containing monosaccharides such as glucose, galactose, and mannose) is connected to the outlet of column 2; intermediate component B (containing xylose) is connected to the outlet of column 4; and slow component C (containing arabinose) is connected to the outlet of column 6. Eluent D and xylose mother liquor E flow in the same direction. Figure 1 The flow is clockwise; the five flow ports switch periodically, and the switching order is: eluent D → slow component C → xylose mother liquor E → intermediate component B → fast component A → eluent D.

[0036] Xylose mother liquor E was processed using an SMB system: chromatographic conditions were set as follows: column temperature 60℃; cycle time 350s; column pressure drop 1.5MPa; eluent D was a sodium carbonate-sodium bicarbonate buffer solution with pH 9.5, with a feed flow rate of 115mL / min for eluent D and 25mL / min for xylose mother liquor E; during elution, a total of 2000mL of xylose mother liquor E containing 822.5g xylose and 324.8g arabinose was purged. Separation using the SMB system yielded the fast fraction A, which included glucose, galactose, mannose, and other miscellaneous sugars; subsequently, the intermediate fraction B and the slow fraction C were obtained.

[0037] Intermediate component B was concentrated via membrane evaporation, followed by vacuum evaporation at 0.04 MPa and 55 °C for 1.5 h, yielding 808.6 g of concentrated intermediate component solution. The xylose purity in the concentrated intermediate component solution was 98.5 wt%, with a recovery rate of 96.8%. Slow component C was concentrated via membrane evaporation, followed by vacuum evaporation at 0.04 MPa and 55 °C for 1.5 h, yielding 316.2 g of concentrated slow component solution. The arabinose purity in the concentrated slow component solution was 96.5 wt%, with a recovery rate of 93.9%.

[0038] The intermediate component concentrate and the slow component concentrate were crystallized, centrifuged, and dried to obtain the finished xylose and finished arabinose.

[0039] Example 2 1. Preparation of phenylboronic acid modified resin (1) Take 1000g of Na + Type S-DVB resin and 1100g of chloromethyl octyl ether were added to a reaction vessel, followed by the addition of 10.5L of toluene. The mixture was stirred and allowed to swell at 120rpm and 35℃ for 35min. After swelling was complete, 90g of anhydrous zinc chloride was added, and the mixture was reacted at 95rpm and 50℃ for 2.5h. After the reaction was complete, the mixture was filtered. The resin was then washed three times in toluene for 8min each time. Finally, it was dried until there was no change in weight to obtain the chloromethylated resin.

[0040] (2) Prepare mixed solvent A with a volume ratio of water:ethanol = 1:2.8 for later use; put 1000g of chloromethylated resin into another reaction vessel, add 4.5L of mixed solvent A, purge with nitrogen, start stirring, and swell at 60rpm and 35℃ for 30min; after swelling is complete, add 530g of ethylenediamine, control the vessel temperature at 60℃, react for 1.5h, and filter after the reaction is complete; then wash in ethanol 3 times, 8min each time; finally dry until there is no change in weight to obtain amination resin.

[0041] (3) Prepare a mixed solvent B with a volume ratio of toluene : N,N-dimethylformamide = 1 : 1.2; mix 1000 g of 4-carboxyphenylboronic acid with 10.5 L of the mixed solvent B, and add 150 g of N,N'-dicyclohexyl carbodiimide and 120 g of N-hydroxysuccinimide, to obtain an activation solution after activation at 35 °C for 15 min. Add 1000 g of the aminated resin to the activation solution, and modify at 45 °C for 2.5 h.

[0042] (4) After modification, take out and add to 5.5 L of anhydrous ethanol together with 260 g of perfluorodecyltriethoxysilane, and keep at 45 °C for 25 min. Then, after filtration, immerse in a 0.8 mol / L sodium chloride solution, and dry until the weight is unchanged, to obtain the phenylboronic acid modified resin.

[0043] 2. Preparation of a modified resin chromatographic column Use the phenylboronic acid modified resin prepared in Example 2 to prepare a modified resin chromatographic column according to the steps in Example 1, and the prepared modified resin chromatographic column is marked as sample 2.

[0044] 3. Single column evaluation test Use the phenylboronic acid modified resin prepared in Example 2, and the specific operation steps are the same as in Example 1. It is proved that the separation degree of xylose, arabinose and other monosaccharides meets the requirements.

[0045] 4. Chromatographic separation The equipment installation steps are the same as in Example 1.

[0046] Use the SMB system to process the xylose mother liquor E: set the chromatographic conditions, wherein the column temperature is 62 °C; the cycle switching time is 340 s; the column pressure drop is 1.2 MPa; the eluent D is a sodium carbonate-sodium bicarbonate buffer solution with pH = 10, the flow rate of the eluent D is 105 mL / min, and the flow rate of the xylose mother liquor E is 30 mL / min; during elution, 2000 mL of the xylose mother liquor E containing 807.0 g of xylose and 295.9 g of arabinose is introduced into the sodium carbonate-sodium bicarbonate buffer solution. After separation by the SMB system, the fast component A including glucose, galactose, mannose and other sugars is obtained first; then the intermediate component B and the slow component C are obtained.

[0047] After the intermediate component B is concentrated by membrane, it is concentrated by vacuum evaporation at 0.04 MPa and 55 °C for 1.5 h, to obtain 782.5 g of the intermediate component concentrate, and the purity of xylose in the intermediate component concentrate is 98.9 wt% and the recovery rate is 95.9%. The slow component C is concentrated by membrane, and then concentrated by vacuum evaporation at 0.04 MPa and 55 °C for 1.5 h, to obtain 284.6 g of the slow component concentrate, and the purity of arabinose in the slow component concentrate is 97.1 wt% and the recovery rate is 93.4%.

[0048] The concentrated solution of the intermediate component and the concentrated solution of the slow component are respectively crystallized, centrifuged and dried to obtain finished xylose and finished arabinose.

[0049] Example 3 1. Preparation of phenylboronic acid modified resin (1) Take 1000g of Na + Type S-DVB resin and 800g of chloromethyloctyl ether into a reaction kettle, continue to add 8.8L of toluene, start stirring, swell for 30min at 60rpm and 25℃; after swelling, add 70g of anhydrous zinc chloride, react for 1.5h at 105rpm and 60℃, and then filter; subsequently, immerse and wash in toluene for 3 times, each for 8min; finally, dry until the weight is unchanged to obtain a chloromethylated resin.

[0050] (2) Prepare mixed solvent A with a volume ratio of water: ethanol = 1:4.5 for standby use; put 1000g of the chloromethylated resin into another reaction kettle, add 4L of mixed solvent A, fill in nitrogen, start stirring, swell for 35min at 30rpm and 25℃; after swelling, add 400g of ethylenediamine, control the kettle temperature at 80℃, react for 1h, and then filter; subsequently, immerse and wash in ethanol for 3 times, each for 8min; finally, dry until the weight is unchanged to obtain an aminated resin.

[0051] (3) Prepare mixed solvent B with a volume ratio of toluene: N,N-dimethylformamide = 1:1.5 for standby use; mix 800g of 4-carboxyphenylboronic acid with 8.5L of mixed solvent B, add 120g of N,N'-dicyclohexyl carbodiimide and 80g of N-hydroxysuccinimide, activate for 30min at 30℃ to obtain an activation liquid. Put 1000g of the aminated resin into the activation liquid, modify for 2h at 40℃.

[0052] (4) After modification, take out and add into 6.5L of anhydrous ethanol together with 150g of perfluorodecyl triethoxysilane, incubate for 45min at 42℃, and then filter, immerse and wash in 0.8mol / L sodium chloride solution, and dry until the weight is unchanged to obtain a phenylboronic acid modified resin.

[0053] 2. Preparation of modified resin chromatographic column Select the phenylboronic acid modified resin prepared in Example 3, and prepare a modified resin chromatographic column according to the steps in Example 1, and the prepared modified resin chromatographic column is marked as sample 3.

[0054] 3. Single column evaluation test Select the phenylboronic acid modified resin prepared in Example 3, and prepare a modified resin chromatographic column according to the steps in Example 1, and the prepared modified resin chromatographic column is marked as sample 3.

[0055] 4. Chromatographic separation The device installation step is the same as in Example 1.

[0056] The xylose mother liquor E was treated using the SMB system: the chromatographic conditions were set with a column temperature of 65°C; a cycle switching time of 300 s; a column pressure drop of 1.1 MPa; eluent D was a sodium carbonate-sodium bicarbonate buffer with a pH of 10.5, the eluent D feed flow rate was 95 mL / min, and the xylose mother liquor E feed flow rate was 35 mL / min; and 2000 mL of the xylose mother liquor E, which contained 845.1 g of xylose and 312.8 g of arabinose, was passed through the sodium carbonate-sodium bicarbonate buffer during elution. After separation by the SMB system, the fast component A, which included glucose, galactose, mannose and other heterosugars, was obtained first, followed by the intermediate component B and the slow component C.

[0057] The intermediate component B was concentrated by membrane concentration and then concentrated by vacuum evaporation at 0.04 MPa and 55°C for 1.5 h to obtain 820.3 g of the intermediate component concentrate, which had a purity of 97.6 wt% and a recovery rate of 94.7% for xylose. The slow component C was concentrated by membrane concentration and then concentrated by vacuum evaporation at 0.04 MPa and 55°C for 1.5 h to obtain 308.7 g of the slow component concentrate, which had a purity of 95.4 wt% and a recovery rate of 94.1% for arabinose.

[0058] The intermediate component concentrate and the slow component concentrate were respectively subjected to crystallization, centrifugal separation and drying to obtain the finished xylose and the finished arabinose.

[0059] Comparative Example 1 Without performing the resin pretreatment and the surface grafting treatment, i.e., without performing steps (1) to (4), a commercially available Na + The remaining steps and the raw materials used were the same as in Example 1 (the single column evaluation test was omitted), and a chromatographic column was prepared and recorded as sample 4. The xylose mother liquor E was treated using the SMB system, and the recovery rate of the xylose was 89.2% and the purity was 91.5%; the recovery rate of the arabinose was 75.8% and the purity was 88.5%.

[0060] Comparative Example 2 Without performing the surface grafting treatment, i.e., without performing steps (3) to (4), the remaining steps and the raw materials used were the same as in Example 1 (the single column evaluation test was omitted), and a chromatographic column was prepared and recorded as sample 5. The xylose mother liquor E was treated using the SMB system, and the recovery rate of the xylose was 80.1% and the purity was 92.3%; the recovery rate of the arabinose was 70.2% and the purity was 90.4%.

[0061] Comparative Example 3 The remaining steps and the raw materials used were the same as in Example 1 (the single column evaluation test was omitted), a chromatographic column was prepared, which was recorded as sample 6, and the xylose mother liquor E was treated using an SMB system, the xylose recovery rate was 81.7%, and the purity was 93.6%; the arabinose recovery rate was 77.3%, and the purity was 92.0%.

[0062] Comparative Example 4 The remaining steps and the raw materials used were the same as in Example 1 (the single column evaluation test was omitted), a chromatographic column was prepared, which was recorded as sample 7, and the xylose mother liquor E was treated using an SMB system, the xylose recovery rate was 82.5%, and the purity was 92.0%; the arabinose recovery rate was 79.1%, and the purity was 90.8%.

[0063] Comparative Example 5 The remaining steps and the raw materials used were the same as in Example 1 (the single column evaluation test was omitted), a chromatographic column was prepared, which was recorded as sample 8, and the xylose mother liquor E was treated using an SMB system, the xylose recovery rate was 89.6%, and the purity was 93.8%; the arabinose recovery rate was 79.7%, and the purity was 87.6%.

[0064] Comparative Example 6 The remaining steps and the raw materials used were the same as in Example 1 (the single column evaluation test was omitted), a chromatographic column was prepared, which was recorded as sample 9, and the xylose mother liquor E was treated using an SMB system, the xylose recovery rate was 74.2%, and the purity was 85.1%; the arabinose recovery rate was 67.4%, and the purity was 85.3%. Implementation effect

[0065] Sample loading test: one chromatographic column prepared in Examples 1-3 and Comparative Examples 1-6 was tested, which was recorded as sample 1-9, the chromatographic conditions were the same as in Example 1, 25wt% methylene blue solution was continuously injected as the feed stream, 8.5mL each time, a total of 60 times; the eluent (pH=9.0 sodium carbonate-sodium bicarbonate buffer) was introduced, the flow rate was 40mL / min, and the total time was 40min, the stable value (P) and the maximum value (P max ) of the column pressure during the whole process were recorded to detect the anti-pollution and regeneration capacity of the chromatographic column.

[0066] The specific chromatographic column performance test results are shown in Table 1.

[0067]

[0068] As shown in Table 1, the column pressure of the application (samples 1-3) increases stably and gently, and the column pressure fluctuation is small. Through the pH response adsorption of phenylboronic acid and the cooperation of the fluorocarbon chain super-hydrophobic interface, the adsorption of pigment macromolecules is significantly reduced, the elution efficiency is improved, the pigment macromolecules can be stripped, the chromatographic column is prevented from being blocked, and the long-term stable operation of the chromatographic column is ensured.

Claims

1. A process for separating xylose mother liquor by chromatography, characterized in that, Includes the following steps: S1. Preparation of phenylboronic acid modified resin; S2. Phenylboronic acid modified resin is packed into a chromatographic column to prepare a modified resin chromatographic column; S3. Install a modified resin column in a simulated moving bed chromatography system and separate the fast component, intermediate component and slow component from the xylose mother liquor; S4. Concentrate the intermediate component and the slow component separately to obtain the intermediate component concentrate and the slow component concentrate.

2. The process for separating xylose mother liquor by chromatography according to claim 1, characterized in that, The preparation of phenylboronic acid modified resin includes the following steps: (1) Styrene-divinylbenzene copolymer resin, chloromethylating agent and organic solvent A are mixed and swollen, and then a catalyst is added to carry out chloromethylation. After chloromethylation is completed, chloromethylated resin is obtained by purification. (2) Prepare mixed solvent A for later use. Mix the chloromethylated resin and mixed solvent A together to swell. Then add the amination reagent to perform amination. After amination is completed, purify to obtain the amination resin. (3) Prepare mixed solvent B for later use. Mix 4-carboxyphenylboronic acid, carboxyl activator, amidation accelerator and mixed solvent B together for activation to obtain an activation solution. Add the amination resin to the activation solution for modification. (4) After modification, the amination resin and hydrophobic coupling agent are mixed with organic solvent B and kept warm to obtain phenylboronic acid modified resin.

3. The process for separating xylose mother liquor by chromatography according to claim 2, characterized in that, In step (1), the styrene-divinylbenzene copolymer resin is a sodium ion-type styrene-divinylbenzene copolymer resin, the chloromethylating agent is chloromethyl octyl ether, the catalyst is anhydrous zinc chloride, and the organic solvent A is toluene; the ratio of the amount of styrene-divinylbenzene copolymer resin, chloromethylating agent, catalyst and mixed solvent A is 1:(0.8~1.1):(0.07~0.09):(8.8~10.5), the styrene-divinylbenzene copolymer resin, chloromethylating agent and catalyst are in g, and the organic solvent A is in L.

4. The process for separating xylose mother liquor by chromatography according to claim 2, characterized in that, In step (1), the swelling stirring rate is 60~120 rpm, the swelling temperature is 25~35℃, and the swelling time is 30~35 min; the chloromethylation stirring rate is 80~105 rpm, the chloromethylation temperature is 50~60℃, and the chloromethylation time is 1.5~2.5 h.

5. The process for separating xylose mother liquor by chromatography according to claim 2, characterized in that, In step (2), mixed solvent A is prepared according to the volume ratio of water:ethanol = 1:(2.8~4.5). The amination reagent is ethylenediamine. The ratio of the amount of chloromethylated resin, amination reagent and mixed solvent A added is 1000:(400~530):(4~4.5). The chloromethylated resin and amination reagent are calculated in g, and mixed solvent A is calculated in L.

6. The process for separating xylose mother liquor by chromatography according to claim 2, characterized in that, In step (2), the swelling stirring rate is 30~60 rpm, the swelling temperature is 25~35℃, and the swelling time is 30~35 min; the amination temperature is 60~80℃, and the amination time is 1~1.5 h.

7. The process for separating xylose mother liquor by chromatography according to claim 2, characterized in that, In step (3), mixed solvent B is prepared according to the volume ratio of toluene: N,N-dimethylformamide = 1:(1.2~1.5). The carboxyl activator is N,N'-dicyclohexylcarbodiimide, and the amidation agent is N-hydroxysuccinimide. The ratio of the amount of amination resin, 4-carboxyphenylboronic acid, carboxyl activator, amidation agent and mixed solvent B is 1000:(800~1000):(120~150):(80~120):(8.5~10.5), where the amination resin, 4-carboxyphenylboronic acid, carboxyl activator and amidation agent are in g, and mixed solvent B is in L. The activation temperature is 30~35℃, the activation time is 15~30min, the modification temperature is 40~45℃, and the modification time is 2~2.5h.

8. The process for separating xylose mother liquor by chromatography according to claim 2, characterized in that, In step (4), the hydrophobic coupling agent is perfluorodecyltriethoxysilane, and the organic solvent B is anhydrous ethanol; the ratio of the amount of amination resin, hydrophobic coupling agent and organic solvent B is 1000:(150~260):(5.5~6.5); the heat preservation temperature is 42~45℃, and the heat preservation time is 25~45min.

9. The process for separating xylose mother liquor by chromatography according to claim 1, characterized in that, The simulated moving bed chromatography system includes five main components and six modified resin columns. The five main components consist of a fast component (A), an intermediate component (B), a slow component (C), an eluent (D), and a xylose mother liquor (E). The six columns include a first column (1), a second column (2), a third column (3), a fourth column (4), a fifth column (5), and a sixth column (6).

10. The process for separating xylose mother liquor by chromatography according to claim 9, characterized in that, The modified resin column temperature is 60~65℃, and the column pressure drop is 1.1~1.5MPa; the eluent is a sodium carbonate-sodium bicarbonate buffer with pH=9.5~10.5, the feed flow rate of the eluent is 95~115mL / min, and the feed rate of xylose mother liquor is 25~35mL / min.

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