A method for separating vitamin C and gulonic acid from vitamin C mother liquor using simulated moving bed technology

Abstract

The present invention relates to the technical field of separation and purification, and provides a method for separating vitamin C and gulonic acid from vitamin C mother liquor by using simulated moving bed technology. The present invention uses water as eluent and adopts a simulated moving bed to separate vitamin C and gulonic acid in vitamin C mother liquor. The method is simple, easy to operate, does not produce acidic waste liquid, does not pollute the environment, and the simulated moving bed occupies a small area, has a high degree of automation, and has low labor intensity; and the present invention strictly controls the operation procedure of the simulated moving bed chromatographic separation system, which can achieve rapid and effective separation of vitamin C and gulonic acid, and can decolorize the sample at the same time, and save eluent. The results of the embodiment show that the purity of vitamin C can reach more than 97%, the yield can reach more than 93%, the purity of gulonic acid can reach more than 97%, and the yield can reach more than 83% when the method of the present invention is used to separate vitamin C and gulonic acid from vitamin C mother liquor.

Description

Technical Field

[0001] The invention relates to the technical field of separation and purification, and in particular to a method for separating vitamin C and gulonic acid from a vitamin C mother liquor by utilizing a simulated moving bed technology. Background Art

[0002] Vitamin C (AscorbicAcid), also known as L-ascorbic acid, is a water-soluble vitamin and one of the essential elements for maintaining life activities. It can promote the biosynthesis of collagen, facilitate faster healing of tissue wounds, promote the metabolism of tyrosine and tryptophan in amino acids, and prolong the life of the body. It improves the utilization of iron, calcium and folic acid, improves the metabolism of fats and lipids, especially cholesterol, and prevents cardiovascular disease. It promotes the growth of teeth and bones, prevents gum bleeding, and prevents joint pain, back pain and leg pain. It enhances the body's anti-stress ability and immunity to the external environment.

[0003] The industrial production of vitamin C generally adopts a two-step fermentation method, and a large amount of vitamin C mother liquor is produced during the crystallization process of crude vitamin C. Vitamin C mother liquor contains two useful ingredients, gulonic acid and vitamin C, as well as a large amount of impurities such as pigments and organic acids, which are difficult to recycle. However, if it is discharged directly, it will cause serious pollution and waste.

[0004] A Chinese patent with publication number CN101041649 A provides a method for recovering vitamin C and gulonic acid from a vitamin C mother liquor, wherein the vitamin C mother liquor to be recovered is diluted with water, then pumped into an anion exchange resin, rinsed with water to obtain vitamin C, and then acid resolved to obtain gulonic acid. This method has complex steps, requires a large amount of acid, generates a lot of waste liquid, and is highly harmful to the environment. Summary of the invention

[0005] In view of this, the present invention provides a method for separating vitamin C and gulonic acid from vitamin C mother liquor using simulated moving bed technology. The method provided by the present invention has simple process, no need to use acid, no environmental pollution, and high purity and yield of gulonic acid and vitamin C.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] A method for separating vitamin C and gulonic acid from a vitamin C mother liquor using a simulated moving bed technology comprises the following steps:

[0008] The vitamin C mother liquor is introduced into a simulated moving bed chromatography separation system, and water is used as an eluent for separation to obtain vitamin C and gulonic acid; the stationary phase of the simulated moving bed chromatography separation system is a metal chelate resin;

[0009] The simulated moving bed chromatography separation system is provided with n chromatographic columns connected in series, which are sequentially recorded as column 1 to column n, wherein n≥6; each chromatographic column is provided with a feed inlet, a water inlet, a circulation port and a discharge port;

[0010] The operation procedure of the simulated moving bed chromatography separation system includes several separation cycles; each separation cycle includes a double-input and double-output stage, a circulation stage and a water-input and gulonic acid-output stage performed in sequence;

[0011] In the first separation cycle, water is introduced into the water inlet of column 1 at the double-input and double-output stage, vitamin C mother liquor is introduced into the feed inlet of column 4, vitamin C is received at the feed outlet of column 1, and gluconic acid is received at the feed outlet of column 5; in the circulation stage, materials are not introduced or discharged, and materials in the chromatographic columns circulate; in the water-input and gluconic acid-output stage, water is introduced into the water inlet of column 2, and gluconic acid is received at the feed outlet of column 6;

[0012] After the first separation cycle is completed, the feed inlet for vitamin C mother liquor, the water inlet, and the outlet for receiving vitamin C or citric acid are moved to the next column in sequence along the direction of column 1 to column n, repeating the double-inlet and double-outlet stage, the circulation stage, and the water inlet and citric acid outlet stage to complete the next separation cycle until the separation is completed.

[0013] Preferably, in each separation cycle, the time of the double-input and double-output stage is 100 to 2000 s, the pumping flow rate of the vitamin C mother solution is 10 to 40 mL / min, and the pumping flow rate of water is 10 to 60 mL / min.

[0014] Preferably, in each separation cycle, the duration of the circulation stage is 200 to 3000 s, and the circulation flow rate of the material in the chromatographic column is 10 to 50 mL / min.

[0015] Preferably, in each separation cycle, the time for the water inlet and outlet citric acid stage is 10 to 500 s, and the water pumping flow rate is 5 to 50 mL / min.

[0016] Preferably, the vitamin C mother liquor is diluted before separation, the dilution multiple is 5 to 20 times, and the concentration of vitamin C in the vitamin C mother liquor dilution obtained by dilution is 20 to 150 g / L.

[0017] Preferably, the volume of each of the chromatographic columns is 400-800 mL.

[0018] Preferably, the operating temperature of the simulated moving bed chromatography separation system is 40-80° C., and the system pressure is 0.1-1.2 MPa.

[0019] Preferably, the resin skeleton of the metal chelate resin is a styrene structure, and the metal ion is Al 3+ , Ca2+ , Fe 2+ , Fe 3+ Mg 2+ 、Ni 2+ Sn 2+ 、Zn 2+ Br 2+ , Pb 2+ , Cu 2+ or K + .

[0020] Preferably, the metal chelate resin is pretreated before use, and the pretreatment method comprises: soaking the metal chelate resin in ethanol and then loading it into a column, and then washing it with ethanol and deionized water in sequence.

[0021] The present invention provides a method for separating vitamin C and gulonic acid from vitamin C mother liquor by using simulated moving bed technology; the present invention uses water as eluent and uses simulated moving bed to separate vitamin C and gulonic acid in vitamin C mother liquor, the method is simple, easy to operate, low cost, no acidic waste liquid is generated, no pollution to the environment, and the simulated moving bed occupies a small area, has a high degree of automation, low labor intensity, and a hygienic working environment; and the present invention strictly controls the operation procedure of the simulated moving bed chromatographic separation system, can achieve rapid and effective separation of vitamin C and gulonic acid, can decolorize the sample at the same time, and save eluent. The results of the embodiment show that the purity of vitamin C can reach more than 97%, the yield can reach more than 93%, the purity of gulonic acid can reach more than 97%, and the yield can reach more than 83% when the method of the present invention is used to separate vitamin C and gulonic acid from vitamin C mother liquor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the operation of the double-input and double-output stage;

[0023] Figure 2 It is a schematic diagram of the operation of the cycle stage;

[0024] Figure 3 This is the operation diagram of the water inlet and gulonic acid outlet stages. DETAILED DESCRIPTION

[0025] The present invention provides a method for separating vitamin C and gulonic acid from a vitamin C mother liquor by using a simulated moving bed technology, comprising the following steps:

[0026] The vitamin C mother liquor is introduced into a simulated moving bed chromatography separation system, and water is used as an eluent for separation to obtain vitamin C and gulonic acid; the stationary phase of the simulated moving bed chromatography separation system is a metal chelate resin;

[0027] The simulated moving bed chromatography separation system is provided with n chromatographic columns connected in series, which are sequentially recorded as column 1 to column n, wherein n≥6; each chromatographic column is provided with a feed inlet, a water inlet, a circulation port and a discharge port;

[0028] The operation procedure of the simulated moving bed chromatography separation system includes several separation cycles; each separation cycle includes a double-input and double-output stage, a circulation stage, and a water-input and gulonic acid-output stage, which are performed in sequence:

[0029] In the first cycle, water is introduced into the water inlet of column 1 at the double-input and double-output stage, vitamin C mother liquor is introduced into the feed inlet of column 4, vitamin C is received at the feed outlet of column 1, and gluconic acid is received at the feed outlet of column 5; in the circulation stage, materials are not introduced or discharged, and materials in the chromatographic columns circulate; in the water-input and gluconic acid-output stage, water is introduced into the water inlet of column 2, and gluconic acid is received at the feed outlet of column 6;

[0030] After the first separation cycle is completed, the feed inlet of the vitamin C mother liquor, the water inlet and the discharge port are moved to the next column in sequence along the direction of column 1 to column n, repeating the double-inlet and double-outlet stage, the circulation stage and the water inlet and citric acid outlet stage to complete the next separation cycle until the separation is completed.

[0031] In the present invention, the vitamin C mother solution is preferably diluted before separation, the dilution multiple is preferably 5 to 20 times, more preferably 10 to 15 times, and the concentration of vitamin C in the vitamin C mother solution dilution obtained by dilution is preferably 20 to 150 g / L, more preferably 50 to 100 g / L. In a specific embodiment of the present invention, it is preferred that the vitamin C mother solution and deionized water are stirred and mixed, and then filtered to remove insoluble matter to obtain the vitamin C mother solution dilution.

[0032] In the present invention, the stationary phase of the simulated moving bed chromatographic separation system is a metal chelate resin, the resin skeleton of the metal chelate resin is preferably a styrene structure, and the metal ion is preferably Al 3+ , Ca 2+ , Fe 2+ , Fe 3+ Mg 2+ 、Ni 2+ Sn 2+ 、Zn 2+ Br 2+ , Pb 2+ , Cu 2+ or K +The metal chelate resin is preferably pretreated before use, and the pretreatment method preferably comprises: soaking the metal chelate resin in ethanol and then loading it into a column, and then using ethanol and deionized water for flow washing in sequence; the volume fraction of the ethanol used for the soaking and flow washing is preferably greater than 95%; the soaking time is preferably 5 to 8 hours, more preferably 6 hours, and stirring is preferably performed continuously during the soaking process to fully swell the metal chelate resin. After the soaking is completed, the ethanol is discarded and the swollen metal chelate resin is loaded into a column; when the ethanol is used for flow washing, it is preferably flow washed until the effluent at the lower end of the chromatography column is no longer turbid when dripped into water, and then the ethanol flow washing can be stopped; when the deionized water is used for flow washing, it is preferably washed until there is no alcohol taste.

[0033] In the present invention, the simulated moving bed chromatography separation system is provided with n chromatographic columns connected in series, and the n chromatographic columns are connected in series with each other, and the head and tail form a closed system, which are sequentially recorded as column No. 1 to column No. n, wherein n≥6, preferably 6-8, and more preferably 6; the volume of each of the chromatographic columns is preferably 400-800 mL, and more preferably 700 mL; each chromatographic column is provided with a feed inlet, a water inlet, a circulation port and a discharge port; the chromatographic column is preferably insulated by a jacket so that the temperature of the entire system is constant; in a specific embodiment of the present invention, the simulated moving bed chromatography separation system is controlled by a computer system; the method of introducing the vitamin C mother liquor into the simulated moving bed chromatography separation system is preferably pumping.

[0034] In the present invention, the operation procedure of the simulated moving bed chromatography separation system includes several separation cycles; each separation cycle includes a double-input and double-output stage, a circulation stage and a water-input and gulonic acid-output stage performed in sequence. The operation schematic diagram of the double-input and double-output stage, the circulation stage and the water-input and gulonic acid-output stage is shown in FIG. Figures 1 to 3 shown.

[0035] In the present invention, in the first separation cycle, in the double-inlet and double-outlet stage, water is introduced into the water inlet of column No. 1, vitamin C mother liquor is introduced into the feed port of chromatographic column No. 4, vitamin C is received at the discharge port of column No. 1, and citric acid is received at the discharge port of column No. 5; in the circulation stage, no material is introduced or discharged, and the material in the chromatographic column circulates; in the water-inlet and citric acid-out stage, water is introduced into the water inlet of column No. 2, and citric acid is received at the discharge port of column No. 6. After the first separation cycle is completed, the feed inlet for vitamin C mother liquor, the water inlet, and the outlet for receiving vitamin C or citric acid are all moved to the next column in the direction from column 1 to column n, and the double-input and double-output stage, the circulation stage, and the water inlet and citric acid outlet stage are repeated to complete the next separation cycle until the separation is completed; for example, when the number of chromatographic columns is 6, in the second separation cycle, water is introduced into the water inlet of column 2 in the double-input and double-output stage, vitamin C mother liquor is introduced into the feed inlet of chromatographic column 5, vitamin C is received at the outlet of column 2, and citric acid is received at the outlet of column 6. ; During the circulation stage, materials neither enter nor exit the chromatographic column, and the materials circulate in the chromatographic column; during the water inlet and citric acid outlet stage, water is introduced at the water inlet of column 3, and citric acid is received at the outlet of column 1; the third cycle is repeated in this way until the separation is completed; in a specific embodiment of the present invention, completing the above-mentioned double-inlet and double-outlet stage, the circulation stage, and the water inlet and citric acid outlet stage is recorded as a small cycle. When all n chromatographic columns in the simulated moving bed chromatographic separation system have undergone a small cycle, it is recorded as a large cycle. After a large cycle is completed, the next large cycle is carried out according to the same procedure until the material processing is completed.

[0036] In the present invention, in each separation cycle (i.e., small cycle), the time of the double-input and double-output stage is preferably 100-2000s, more preferably 200-1500s, the pumping flow rate of the vitamin C mother solution is preferably 10-40mL / min, more preferably 10-30mL / min; the pumping flow rate of water is preferably 10-60mL / min, more preferably 30-40mL / min. The present invention separates the discharge positions of vitamin C and gulonic acid through the double-input and double-output stage to avoid cross contamination.

[0037] In the present invention, in each separation cycle, the time of the circulation stage is preferably 200 to 3000 seconds, more preferably 500 to 2000 seconds, and the circulation flow rate of the material in the chromatographic column is preferably 10 to 50 mL / min, more preferably 30 to 40 mL / min. In the present invention, the liquid flow direction of the material in the chromatographic column in the circulation stage is from column 1 to column n, and the solvent in the chromatographic column circulates to continue to separate vitamin C and citric acid, thereby saving the eluent.

[0038] In the present invention, in each separation cycle, the time of the water inlet and gulonic acid outlet stage is preferably 10 to 500 seconds, more preferably 50 to 400 seconds; the water pumping flow rate is preferably 5 to 50 mL / min, more preferably 10 to 40 mL / min. In the water inlet and gulonic acid outlet stage, the slow component (i.e., vitamin C) is further purified and separated at the water inlet end, which is also beneficial to increase the yield of the fast component (i.e., gulonic acid).

[0039] In the present invention, the operating temperature of the simulated moving bed chromatography separation system is preferably 40-80° C., more preferably 50° C., and the system pressure is preferably 0.1-1.2 MPa, more preferably 1.05 MPa.

[0040] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Example 1

[0042] Take 2L of vitamin C mother solution, add 10L of deionized water to make the vitamin C content 80g / L, stir well, filter to remove insoluble matter, and obtain a vitamin C mother solution dilution;

[0043] Take K + 5L of chelating resin is filled with 6 700mL jacketed chromatography columns, which are soaked with ethanol with a content greater than 95% for 6h, and stirred continuously to fully swell the resin, then the ethanol is discarded, the resin is loaded into a chromatography column, and the ethanol with a content greater than 95% is used for flow washing, when the outflow from the lower end of the chromatography column is no longer turbid when dripped into water, the ethanol washing is terminated, and the resin pretreatment is completed after washing with deionized water until there is no alcohol taste;

[0044] Pump the vitamin C stock solution dilution into the K + In the simulated moving bed chromatography separation system with chelating resin as the stationary phase, water is used as the eluent, the separation temperature is set to 50°C, the system pressure is 1.05MPa, and the simulated moving bed chromatography separation system is operated according to the procedures of double inlet and double outlet, circulation, and water inlet and gulonic acid outlet. After each small cycle, the feed inlet, water inlet and outlet for receiving vitamin C or gulonic acid are moved one chromatographic column in turn to carry out the next small cycle. After all 6 chromatographic columns have run a small cycle, it is recorded as a large cycle.

[0045] System parameter settings are shown in Table 1.

[0046] Table 1 Parameter settings of simulated moving bed chromatography separation system

[0047]

[0048]

[0049] The system reached equilibrium after running 3 large cycles. The results at equilibrium were: vitamin C was colorless and had a purity of 99.80%; gulonic acid was colorless and had a purity of 98.5%. After the treatment was completed, the yields of vitamin C and gulonic acid were calculated, and the results were: vitamin C yield was 95%, and gulonic acid yield was 83%.

[0050] Example 2

[0051] Take 2L of vitamin C mother solution, add 10L of deionized water to make the vitamin C content 120g / L, stir well, filter to remove insoluble matter, and obtain a vitamin C mother solution dilution;

[0052] Take Ca 2+ 5L of chelating resin is filled with 6 700mL jacketed chromatography columns, which are soaked with ethanol with a content greater than 95% for 6h, and stirred continuously to fully swell the resin, then the ethanol is discarded, the resin is loaded into a chromatography column, and the ethanol with a content greater than 95% is used for flow washing, when the outflow from the lower end of the chromatography column is no longer turbid when dripped into water, the ethanol washing is terminated, and the resin pretreatment is completed after washing with deionized water until there is no alcohol taste;

[0053] The vitamin C mother liquor dilution was pumped into a simulated moving bed chromatography separation system with a metal chelate resin as the stationary phase, water was used as the eluent, the separation temperature was set to 50°C, and the system pressure was set to 1.05 MPa. The operating procedure of the simulated moving bed chromatography separation system was similar to that of Example 1, and only the operating parameters were adjusted. The system parameter settings are shown in Table 2.

[0054] Table 2 Parameter settings of simulated moving bed chromatography separation system

[0055]

[0056] The system reached equilibrium after running 3 large cycles. The results at equilibrium were: vitamin C was colorless and had a purity of 97%; gulonic acid was colorless and had a purity of 97.5%. After the treatment was completed, the yields of vitamin C and gulonic acid were calculated, and the results were: vitamin C yield was 93.00% and gulonic acid yield was 85%.

[0057] Example 3

[0058] Take 2L of vitamin C mother solution, add 10L of deionized water to make the vitamin C content 150g / L, stir well, filter to remove insoluble matter, and obtain a vitamin C mother solution dilution;

[0059] Take Ca 2+5L of chelating resin is filled with 6 700mL jacketed chromatography columns, which are soaked with ethanol with a content greater than 95% for 6h, and stirred continuously to fully swell the resin, then the ethanol is discarded, the resin is loaded into a chromatography column, and the ethanol with a content greater than 95% is used for flow washing, when the outflow from the lower end of the chromatography column is no longer turbid when dripped into water, the ethanol washing is terminated, and the resin pretreatment is completed after washing with deionized water until there is no alcohol taste;

[0060] The vitamin C mother liquor dilution was pumped into a simulated moving bed chromatography separation system with a metal chelate resin as the stationary phase, water was used as the eluent, the separation temperature was set to 50°C, and the system pressure was set to 1.05 MPa. The operating procedure of the simulated moving bed chromatography separation system was similar to that of Example 1, and only the operating parameters were adjusted. The system parameter settings are shown in Table 3.

[0061] Table 3 Parameter settings of simulated moving bed chromatography separation system

[0062]

[0063] The system reached equilibrium after running 3 large cycles. The results at equilibrium were: vitamin C was colorless and had a purity of 98.75%; gulonic acid was colorless and had a purity of 97.2%. After the treatment was completed, the yields of vitamin C and gulonic acid were calculated, and the results were: vitamin C yield was 95%, and gulonic acid yield was 87.5%.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for separating vitamin C and gulonic acid from vitamin C mother liquor using simulated moving bed technology, characterized in that: The following steps are involved: The vitamin C mother liquor is introduced into a simulated moving bed chromatography separation system, and water is used as an eluent for separation to obtain vitamin C and gulonic acid; the stationary phase of the simulated moving bed chromatography separation system is a metal chelate resin; The simulated moving bed chromatography separation system is provided with n chromatographic columns connected in series, which are sequentially recorded as column 1 to column n, wherein n=6; each chromatographic column is provided with a feed inlet, a water inlet, a circulation port and a discharge port; The operation procedure of the simulated moving bed chromatography separation system includes several separation cycles; each separation cycle includes a double-input and double-output stage, a circulation stage and a water-input and gulonic acid-output stage performed in sequence; In the first separation cycle, water is introduced into the water inlet of column 1 at the double-input and double-output stage, vitamin C mother liquor is introduced into the feed inlet of column 4, vitamin C is received at the feed outlet of column 1, and gluconic acid is received at the feed outlet of column 5; in the circulation stage, materials are not introduced or discharged, and materials in the chromatographic columns circulate; in the water-input and gluconic acid-output stage, water is introduced into the water inlet of column 2, and gluconic acid is received at the feed outlet of column 6; After the first separation cycle is completed, the feed inlet for the vitamin C mother liquor, the water inlet, and the outlet for receiving the vitamin C or gulonic acid are all moved to the next column in the direction from column 1 to column n, and the double-inlet and double-outlet stage, the circulation stage, and the water inlet and gulonic acid outlet stage are repeated to complete the next separation cycle until the separation is completed; In each separation cycle, the time of the double-input and double-output stage is 100 to 2000 seconds, the pumping flow rate of the vitamin C mother solution is 10 to 40 mL / min, and the pumping flow rate of water is 10 to 60 mL / min; In each separation cycle, the cycle phase lasts for 200 to 3000 seconds, and the circulation flow rate of the material in the chromatographic column is 10 to 50 mL / min; In each separation cycle, the time for the water inlet and outlet of the citric acid stage is 10 to 500 seconds, and the water pumping flow rate is 5 to 50 mL / min.

2. The method according to claim 1, characterized in that The vitamin C mother liquor is diluted and then separated, the dilution multiple is 5 to 20 times, and the concentration of vitamin C in the vitamin C mother liquor dilution obtained by dilution is 20 to 150 g / L.

3. The method according to claim 1, characterized in that The volume of each chromatographic column is 400-800 mL.

4. The method according to claim 1, characterized in that: The operating temperature of the simulated moving bed chromatography separation system is 40-80° C., and the system pressure is 0.1-1.2 MPa.

5. The method according to claim 1, characterized in that The resin skeleton of the metal chelate resin is a styrene structure, and the metal ion is Al 3+ , Ca 2+ , Fe 2+ , Fe 3+ Mg 2+ 、Ni 2+ Sn 2+ 、Zn 2+ Br 2+ , Pb 2+ , Cu 2+ or K + .

6. The method according to claim 1 or 5, characterized in that: The metal chelate resin is pretreated before use, and the pretreatment method comprises: soaking the metal chelate resin in ethanol and then packing it into a column, and then washing it with ethanol and deionized water in sequence.

Images