Method for combined treatment of scutellaria baicalensis acidification waste liquid by adopting membrane technology and simulated moving bed

Abstract

The invention discloses a method for jointly treating scutellaria baicalensis acidification waste liquid by adopting a membrane technology and a simulated moving bed. The method comprises the following steps: adjusting the pH value of the scutellaria baicalensis acidification waste liquid and cooling to obtain a pretreatment solution; concentrating the pretreatment solution to obtain permeate I; concentrating the permeate liquid I to obtain permeate liquid II and trapped liquid II; adjusting the pH value of the trapped fluid II to obtain a to-be-treated fluid; separating by adopting a simulated moving bed chromatographic separation system, and collecting an organic phase and an organic salt phase; adjusting the pH value of the organic salt phase, filtering through a nanofiltration membrane to obtain trapped fluid III and permeated fluid III, and treating the trapped fluid III to obtain scutellaria baicalensis flavone; concentrating the organic phase to obtain trapped fluid IV and permeated fluid IV, and treating the trapped fluid IV to obtain scutellaria baicalensis polysaccharide; combining and concentrating the second permeate and the third permeate to obtain a fifth trapped fluid and a fifth permeate, and treating the fifth trapped fluid to obtain potassium chloride. The membrane technology and the simulated moving bed are combined for treatment, effective components in the scutellaria baicalensis acid precipitation waste liquid are recycled, the economic value of the scutellaria baicalensis acid precipitation waste liquid is greatly increased, and the scutellaria baicalensis acid precipitation waste liquid is prevented from being directly discharged to pollute the environment.

Description

Technical Field

[0001] The invention relates to the technical field of resource recycling, and in particular to a method for treating baicalin acidification waste liquid by combining membrane technology with a simulated moving bed. Background Art

[0002] Scutellaria baicalensis is a perennial herbaceous plant of the genus Scutellaria in the Lamiaceae family. It is also known as the root of camellia. It is cold in nature and bitter in taste. It belongs to the lung, heart, liver, and large intestine meridians. It has the effects of clearing away heat and dampness, purging fire and detoxifying, stopping bleeding and calming the fetus. It is a cooling and antipyretic medicine. Scutellaria baicalensis contains a variety of active chemical components. At present, more than 40 flavonoid components with structures have been identified, mainly baicalin, wogonin, baicalein, wogonin, etc. Studies have shown that the content of the above four flavonoids accounts for 10.11%, 2.41%, 0.55% and 0.37% of the medicinal materials, respectively. At present, most pharmaceutical factories use Scutellaria baicalensis medicinal materials to produce monomer baicalin, and a large amount of baicalic acid precipitate is directly discarded, causing environmental pollution. There are also a large amount of baicalin, wogonin, baicalein, and wogonin in the baicalic acid precipitate. Direct discharge will cause great waste of resources and loss of economic benefits. Therefore, how to reuse the waste liquid from the acid precipitation of Scutellaria baicalensis is of great significance.

[0003] The patent with application number 201910196656.8 provides a method for recovering Scutellaria polysaccharide from baicalin production waste liquid, comprising the following steps: Step 1: Filter and concentrate the baicalin production waste liquid, and adjust the pH value to 6.0-7.0; Step 2: Add ethanol to the concentrated solution, refrigerate at low temperature, filter, and take the filter cake for later use; Step 3: Bake the filter cake at 30-50°C for 3-15h, add water and stir to dissolve, filter with primary activated carbon, and then filter with secondary microfiltration to obtain a filtrate; Step 4: Adsorb the filtrate through a macroporous resin, pass a low concentration salt for elution, and collect the eluate; Step 5: Perform primary microfiltration on the eluate, collect the filtrate, perform secondary ultrafiltration, collect the retentate, and concentrate and dry the retentate to obtain Scutellaria polysaccharide. Although the above method can recover the scutellaria polysaccharide in the waste liquid, the operation process is relatively complicated, and other effective components in the waste liquid are not effectively recovered, and the scutellaria acid precipitation waste liquid is not fully utilized. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in view of the shortcomings of the prior art, a method for treating baicalin acid precipitated waste liquid by using membrane technology and simulated moving bed is provided. The method recovers the effective components in the baicalin acid precipitated waste liquid by using membrane technology and simulated moving bed for combined treatment through effectively controlling conditions, thereby greatly improving the economic value of the baicalin acid precipitated waste liquid and preventing it from being directly discharged to pollute the environment.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed, comprising the following steps:

[0007] (1) adjusting the pH of the baicalin acid precipitation waste liquid to 4.0-5.0, cooling, and obtaining a pretreatment solution;

[0008] (2) using a ceramic membrane to concentrate the pre-treated liquid to 2-3% of the original volume, and collecting the permeate;

[0009] (3) concentrating the permeate 1 by a nanofiltration membrane to obtain a permeate 2 and a retentate 2 having a solid content of 15-25 wt %;

[0010] (4) adjusting the pH of the retentate second to 6.0-6.5 to obtain a liquid to be treated; pumping the liquid to be treated into a simulated moving bed chromatography separation system, using an acrylic resin as a stationary phase and water as a mobile phase, for separation, and collecting an organic phase and an organic salt phase;

[0011] (5) adjusting the pH of the organic salt phase to 4.5-5.0, filtering with a nanofiltration membrane, collecting the retentate three and the permeate three, and concentrating the retentate three by heat and spray drying to obtain scutellaria baicalensis flavonoids;

[0012] (6) The organic phase is concentrated by a reverse osmosis membrane to obtain a retentate solution 4 and a permeate solution 4, and the retentate solution 4 is thermally concentrated and then spray-dried to obtain Scutellaria baicalensis polysaccharide;

[0013] (7) The permeate 2 of step (3) and the permeate 3 of step (5) are combined and concentrated by reverse osmosis membrane to obtain retentate 5 and permeate 5. The retentate 5 is thermally concentrated and then cooled, and then filtered. The filter cake is dried to obtain potassium chloride.

[0014] Preferably, in step (2), the filtration pore size of the ceramic membrane is 5-10 nm, and the concentration pressure is 0.4-0.8 MPa.

[0015] Preferably, in step (3), the molecular weight cutoff of the nanofiltration membrane is 150-300 Da; and / or the membrane pressure during concentration is 3.0-5.0 MPa.

[0016] Preferably, in steps (1) and (4), when adjusting the pH, an alkali solution with a concentration of 10-30 wt% is used for adjustment, and the alkali solution is a mixture of one or more of potassium hydroxide, potassium bicarbonate, and potassium carbonate.

[0017] Preferably, in step (4), the average particle size of the acrylic resin is 350-450 μm; and / or the diameter-to-height ratio of a single column chromatographic column of the simulated mobile chromatography separation system is 1:2-3; and / or the simulated moving bed separation system comprises eight chromatographic columns connected in series and end to end; a cyclic separation process comprises cyclic flushing, water flushing, water analysis, and a feeding process, the water analysis and feeding processes are carried out simultaneously, and the organic salt phase is recovered in the water flushing process and the feeding process, and the organic phase is recovered in the water analysis process.

[0018] Preferably, in step (4), during one circulation process, the flushing amount of the circulating liquid is 43-45 v / v% of the volume of the single column chromatographic column, the flushing amount of water is 15-17 v / v% of the volume of the single column chromatographic column, the water analysis amount is 30-35 v / v% of the volume of the single column chromatographic column, and the feed amount of the treated liquid is 10-12 v / v% of the volume of the single column chromatographic column.

[0019] Preferably, in step (4), based on the volume of resin in a single chromatographic column, the circulating flushing flow rate (Va) is 1.5-2.0 BV / h, the water flushing flow rate (Vb) is 1.5-2.0 BV / h, the water desorption flow rate is 1.5-2.0 BV / h, the feed flow rate (Vd) is 0.5-0.7 BV / h, the circulating flushing time is 12.9-18.0 min, the water flushing time is 4.5-6.8 min, the water desorption time (feeding time) is 9.0-14.0 min, and then switching to the next cycle.

[0020] Preferably, in step (5), a hydrochloric acid solution with a concentration of 5-20wt% is used to adjust the pH of the organic salt phase, the molecular weight cutoff of the nanofiltration membrane is 150-300Da, the membrane pressure during filtration using the nanofiltration membrane is 3.0-5.0MPa, and the solid content of the retentate concentrated during filtration is 15-25wt%.

[0021] Preferably, in step (6), the organic phase is concentrated by reverse osmosis membrane to a solid content of 10-20 wt%; thermally concentrated to a solution solid content of 45-60 wt%; and / or the permeate is used as a mobile phase in the simulated moving bed chromatography separation process of step (4).

[0022] Preferably, in step (7), the reverse osmosis membrane is concentrated to a solid content of 5-10 wt%; and / or the permeate five is used as a mobile phase in the simulated moving bed chromatography separation process of step (4); and / or it is thermally concentrated to a solid content of 65-75 wt%; and / or the temperature is lowered to 20-45° C. for precipitation.

[0023] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0024] 1. The present invention uses baicalin acid-precipitated waste liquid as raw material, adopts membrane technology and simulated moving bed combined treatment, recovers baicalin flavonoids and baicalin polysaccharides in the baicalin acid-precipitated waste liquid, and produces potassium chloride as a by-product, effectively improving the economic value of the baicalin acid-precipitated waste liquid.

[0025] 2. The present invention first adjusts the pH value of the baicalin acid precipitation waste liquid, and then cools it to prevent the baicalin substances from precipitating during the cooling process, thereby being intercepted by the ceramic membrane and losing the effective components, thereby improving the recovery rate of the effective products.

[0026] 3. The present invention performs ceramic membrane filtration and nanofiltration membrane filtration on the cooled Scutellaria acid precipitation waste liquid to remove impurities, obtains a retentate with a certain solid content, and then effectively controls the pH of the retentate to obtain a liquid to be treated, and uses simulated moving bed chromatography to separate the liquid under certain conditions, and realizes effective separation of the organic phase and the organic salt phase according to the difference in fluidity between the organic phase and the organic salt phase in the stationary phase and the mobile phase, and preliminarily separates Scutellaria polysaccharide and Scutellaria flavonoids. The above process is simple to operate and has a large single batch processing capacity.

[0027] 4. The present invention first adjusts the pH of the organic salt phase containing baicalin and then concentrates it using a nanofiltration membrane to effectively remove potassium chloride in the organic salt phase, thereby obtaining a high content of baicalin. The reasonable adjustment of pH in this process effectively avoids the oxidation of baicalin by oxygen in the air, and also avoids the precipitation of baicalin under low pH conditions, resulting in product loss.

[0028] 5. Part of the effective waste liquid in the process of the present invention is used to recover the potassium chloride product, and the other part is used as a mobile phase in the simulated moving bed chromatography separation, which effectively reduces the discharge of waste liquid, reduces energy consumption on the one hand, avoids environmental pollution on the other hand, and increases economic benefits. DETAILED DESCRIPTION

[0029] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0030] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present invention, rather than all of the embodiments.

[0031] In the following examples and comparative examples, unless otherwise specified, the raw materials are all commercially available and the conditions are all conventional conditions in the art.

[0032] The simulated moving bed chromatographic separation system in the following embodiments and comparative examples includes eight chromatographic columns connected in series and end to end; the eight chromatographic columns are divided into four zones, namely zone I, zone II, zone III, and zone IV. In one cycle, zone I is the first chromatographic column, zone II includes three chromatographic columns connected in series in sequence, zone III includes three chromatographic columns connected in series in sequence, and zone IV is the tail chromatographic column. A cyclic separation process includes cyclic flushing, water flushing, water analysis, and feeding process. The water analysis and feeding are carried out simultaneously, and the organic salt phase containing scutellaria baicalensis flavonoids is recovered in the water flushing process and the feeding process, and the organic phase containing scutellaria baicalensis polysaccharide is recovered in the water analysis process. During the cyclic flushing, the effluent of the chromatographic column in zone IV enters from the top of the chromatographic column in zone I to flush the eight chromatographic columns connected in series. During the water flushing, the mobile phase enters from the chromatographic column in zone I to flush the chromatographic columns in zones I, II, and III, and the organic salt phase is collected at the bottom of the last chromatographic column in zone III. During the water analysis, water enters from the chromatographic column in zone I to analyze the chromatographic column in zone I, and the organic phase is collected at the bottom of the chromatographic column in zone I. At the same time as the water analysis, the material is fed from the top of the first chromatographic column in zone III, and the organic salt phase is collected at the bottom of the last chromatographic column in zone III.

[0033] Example 1

[0034] A method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed, comprising the following steps:

[0035] (1) adjusting the pH value of 200 kg of scutellaria baicalensis acid-precipitated waste liquid (solid content of the acid-precipitated waste liquid is 4.1 wt %, scutellaria baicalensis flavonoid content in the dry matter is 6.0 wt %, and scutellaria baicalensis polysaccharide content is 11.3 wt %) to 4.7 with 25 wt % K2CO3, and cooling to 43° C. to obtain a pretreated liquid;

[0036] (2) using a ceramic membrane with a pore size of 8 nm under a pressure of 0.5 MPa, the pre-treated liquid was concentrated to 2.2% of the original volume to obtain a permeate solution 1;

[0037] (3) using a nanofiltration membrane with a molecular weight cutoff of 200 Da to concentrate the permeate 1 to a solid content of 22 wt % under a membrane pressure of 4.5 MPa, and then stopping filtering to obtain a permeate 2 and a retentate 2;

[0038] (4) adjusting the pH of the retentate second to 6.3 using 15 wt % KHCO3 to obtain a solution to be treated;

[0039] (5) The treated liquid is pumped into a simulated moving bed chromatography separation system for separation. During separation, the chromatographic column is filled with Lanxiao Technology acrylic resin S2850 with an average particle size of 400 μm, and the diameter-to-height ratio of the single column chromatography column is 2.7. During one cycle, the circulating liquid flushing volume is 44 v / v% of the volume of the single column chromatography column, the water flushing volume is 16 v / v% of the volume of the single column chromatography column, and the water desorption volume is 34 v / v% of the volume of the single column chromatography column. The feed amount of the treated liquid is 11v / v% of the volume of a single column; based on the volume of the resin in a single column, the circulating flushing flow rate (Va) is: 1.8BV / h, the water flushing flow rate (Vb) is 1.8BV / h, the water decomposition flow rate (Vc) is 1.8BV / h, the feed flow rate (Vd) is 0.6BV / h, the circulating flushing time is 14.7min, the water flushing time is 5.3min, the water decomposition time (feeding time) is 11.3min, and then switch to the next cycle;

[0040] (6) The pH of the organic salt phase was adjusted to 4.7 using a 15 wt % hydrochloric acid solution, and then concentrated to a solid content of 22 wt % using a nanofiltration membrane with a molecular weight cutoff of 200 Da at a membrane pressure of 4.5 MPa to obtain a permeate solution 3 and a retentate solution 3; the retentate solution was thermally concentrated to a solid content of 50 wt %, and finally spray-dried to obtain 1036.8 g of scutellaria baicalensis flavonoids, wherein the total scutellaria baicalensis flavonoids content was 46.1 wt %, and the yield was 97.1%;

[0041] (7) using a reverse osmosis membrane to concentrate the solid content of the organic phase to 17 wt % to obtain a retentate 4 and a permeate 4; the retentate 4 was thermally concentrated to a solid content of 54 wt % and finally spray dried to obtain 4012 g of Scutellaria baicalensis polysaccharide with a solid content of 22.8 wt % and a yield of 98.7%; the permeate 4 was used as a mobile phase in the simulated moving bed chromatography separation of step (5);

[0042] (8) The permeate 2 of step (3) and the permeate 3 of step (6) are mixed and concentrated to a solid content of 8 wt% using a reverse osmosis membrane to obtain a retentate 5 and a permeate 5. The retentate 5 is thermally concentrated to a solid content of 72 wt%, then cooled to 31° C. for precipitation until no new precipitate is generated, and filtered to obtain KCl with a content of ≥90%. The permeate 5 is used as a mobile phase in the simulated moving bed chromatography separation of step (5).

[0043] Example 2

[0044] A method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed, comprising the following steps:

[0045] (1) adjusting the pH value of 200 kg of scutellaria baicalensis acid-precipitated waste liquid (solid content of the acid-precipitated waste liquid is 4.1 wt %, scutellaria baicalensis flavonoid content in the dry matter is 6.0 wt %, and scutellaria baicalensis polysaccharide content is 11.3 wt %) to 4.0 with 10 wt % KOH, and cooling to 50° C. to obtain a pretreated liquid;

[0046] (2) using a ceramic membrane with a pore size of 5 nm and a pressure of 0.8 MPa, the pre-treated liquid was concentrated to 2% of the original volume to obtain a permeate solution;

[0047] (3) using a nanofiltration membrane with a molecular weight cutoff of 150 Da to concentrate the permeate 1 to a solid content of 15 wt % under a membrane pressure of 5.0 MPa, and then stopping filtering to obtain a permeate 2 and a retentate 2;

[0048] (4) adjusting the pH of the retentate second to 6.0 using 30 wt % KOH to obtain a solution to be treated;

[0049] (5) The treated liquid is pumped into a simulated moving bed chromatography separation system for separation. During separation, the chromatographic column is filled with Lanxiao Technology acrylic resin S2850 with an average particle size of 350 μm, and the diameter-to-height ratio of the single column chromatography column is 1:2.0. During one cycle, the circulating liquid flushing volume is 45 v / v% of the volume of the single column chromatography column, the water flushing volume is 17 v / v% of the volume of the single column chromatography column, and the water desorption volume is 30 v / v% of the volume of the single column chromatography column. It is 10v / v% of the volume of a single column chromatographic column; based on the volume of the resin in a single chromatographic column, the circulation flushing flow rate (Va) is: 1.5BV / h, the water flushing flow rate (Vb) is 1.5BV / h, the water decomposition flow rate (Vc) is 1.5BV / h, the feed flow rate (Vd) is 0.5BV / h, the circulation flushing time is 18.0min, the water flushing time is 6.8min, the water decomposition time (feeding time) is 12.0min, and then switch to the next cycle;

[0050] (6) The pH of the organic salt phase was adjusted to 5.0 using a 5 wt % hydrochloric acid solution, and then concentrated to a solid content of 15 wt % using a nanofiltration membrane with a molecular weight cutoff of 150 Da at a membrane pressure of 3.0 MPa to obtain permeate 3 and retentate 3; the retentate was thermally concentrated to a solid content of 40 wt %, and finally spray-dried to obtain 1043.7 g of scutellaria baicalensis flavonoids, wherein the total scutellaria baicalensis flavonoids content was 45.5 wt %, and the yield was 96.5%;

[0051] (7) using a reverse osmosis membrane to concentrate the solid content of the organic phase to 10 wt % to obtain a retentate 4 and a permeate 4; the retentate 4 was thermally concentrated to a solid content of 45 wt % and finally spray dried to obtain 3998 g of Scutellaria baicalensis polysaccharide with a solid content of 22.5 wt % and a yield of 97.1%; the permeate 4 was used as a mobile phase in the simulated moving bed chromatography separation of step (5);

[0052] (8) The permeate 2 of step (3) and the permeate 3 of step (6) are mixed and concentrated to a solid content of 5 wt% using a reverse osmosis membrane to obtain a retentate 5 and a permeate 5. The retentate 5 is thermally concentrated to a solid content of 75 wt%, then cooled to 45° C. for precipitation until no new precipitate is generated, and filtered to obtain KCl with a content of ≥90%. The permeate 5 is used as a mobile phase in the simulated moving bed chromatography separation of step (5).

[0053] Example 3

[0054] A method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed, comprising the following steps:

[0055] (1) adjusting the pH value of 200 kg of scutellaria baicalensis acid-precipitated waste liquid (solid content of the acid-precipitated waste liquid is 4.1 wt %, content of scutellaria baicalensis flavonoids in the dry matter is 6.0 wt %, and content of scutellaria baicalensis polysaccharides is 11.3 wt %) to 5.0 with 30 wt % KHCO 3 , and cooling to 40° C. to obtain a pre-treated liquid;

[0056] (2) using a ceramic membrane with a pore size of 10 nm under a pressure of 0.4 MPa, the pre-treated liquid was concentrated to 3% of the original volume to obtain a permeate solution 1;

[0057] (3) using a nanofiltration membrane with a molecular weight cutoff of 300 Da to concentrate the permeate 1 to a solid content of 25 wt % under a membrane pressure of 3.0 MPa, and then stopping the filtration to obtain a permeate 2 and a retentate 2;

[0058] (4) adjusting the pH of the retentate second to 6.5 using 10 wt % KHCO3 to obtain a solution to be treated;

[0059] (5) The treated liquid is pumped into a simulated moving bed chromatography separation system for separation. During separation, the chromatographic column is filled with Lanxiao Technology acrylic resin S2850 with an average particle size of 450 μm, and the diameter-to-height ratio of the single column chromatography column is 1:3.0. During one cycle, the circulating liquid flushing volume is 43 v / v% of the volume of the single column chromatography column, the water flushing volume is 15 v / v% of the volume of the single column chromatography column, and the water desorption volume is 35 v / v% of the volume of the single column chromatography column. The volume of the single column is 12 v / v%; based on the volume of the resin in the single column, the circulation flushing flow rate (Va) is: 2.0 BV / h, the water flushing flow rate (Vb) is 2.0 BV / h, the water decomposition flow rate (Vc) is 2.0 BV / h, the feed flow rate (Vd) is 0.7 BV / h, the circulation flushing time is 12.9 min, the water flushing time is 4.5 min, the water decomposition time (feeding time) is 10.5 min, and then switch to the next cycle;

[0060] (6) The pH of the organic salt phase was adjusted to 4.5 using a 20 wt % hydrochloric acid solution, and then concentrated to a solid content of 25 wt % using a nanofiltration membrane with a molecular weight cutoff of 300 Da at a membrane pressure of 5.0 MPa to obtain a permeate solution 3 and a retentate solution 3; the retentate solution was thermally concentrated to a solid content of 55 wt %, and finally spray-dried to obtain 1048.3 g of scutellaria baicalensis flavonoids, wherein the total scutellaria baicalensis flavonoids content was 45.1 wt %, and the yield was 96.1%;

[0061] (7) using a reverse osmosis membrane to concentrate the solid content of the organic phase to 20 wt % to obtain a retentate 4 and a permeate 4; the retentate 4 was thermally concentrated to a solid content of 60 wt % and finally spray dried to obtain 4092 g of Scutellaria baicalensis polysaccharide with a solid content of 21.9 wt % and a yield of 96.7%; the permeate 4 was used as a mobile phase in the simulated moving bed chromatography separation of step (5);

[0062] (8) The permeate 2 of step (3) and the permeate 3 of step (6) are mixed and concentrated to a solid content of 10 wt % using a reverse osmosis membrane to obtain a retentate 5 and a permeate 5. The retentate 5 is thermally concentrated to a solid content of 65 wt %, then cooled to 20° C. for precipitation until no new precipitate is generated, and filtered to obtain KCl with a content of ≥ 90%. The permeate 5 is used as a mobile phase in the simulated moving bed chromatography separation of step (5).

[0063] Example 4

[0064] A method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed, comprising the following steps:

[0065] (1) adjusting the pH value of 200 kg of scutellaria baicalensis acid-precipitated waste liquid (solid content of the acid-precipitated waste liquid is 4.1 wt %, scutellaria baicalensis flavonoid content in the dry matter is 6.0 wt %, and scutellaria baicalensis polysaccharide content is 11.3 wt %) to 4.2 with 15 wt % K2CO3, and cooling to 47° C. to obtain a pretreated liquid;

[0066] (2) using a ceramic membrane with a pore size of 8 nm under a pressure of 0.6 MPa, the pre-treated liquid was concentrated to 2.5% of the original volume to obtain a permeate solution 1;

[0067] (3) using a nanofiltration membrane with a molecular weight cutoff of 200 Da to concentrate the permeate 1 to a solid content of 17 wt % under a membrane pressure of 3.2 MPa, and then stopping filtering to obtain a permeate 2 and a retentate 2;

[0068] (4) adjusting the pH of the retentate second to 6.2 using 25 wt % K2CO3 to obtain a solution to be treated;

[0069] (5) The treated liquid is pumped into a simulated moving bed chromatography separation system for separation. During separation, the chromatographic column is filled with Lanxiao Technology acrylic resin S2850 with an average particle size of 400 μm, and the diameter-to-height ratio of the single column chromatography column is 1:2.7. During one cycle, the circulating liquid flushing volume is 44 v / v% of the volume of the single column chromatography column, the water flushing volume is 16 v / v% of the volume of the single column chromatography column, and the water desorption volume is 32 v / v% of the volume of the single column chromatography column. The volume of the single column is 12 v / v%; based on the volume of the resin in the single column, the circulation flushing flow rate (Va) is: 1.6 BV / h, the water flushing flow rate (Vb) is 1.6 BV / h, the water decomposition flow rate (Vc) is 1.6 BV / h, the feed flow rate (Vd) is 0.6 BV / h, the circulation flushing time is 16.5 min, the water flushing time is 6.0 min, the water decomposition time (feeding time) is 12.0 min, and then switch to the next cycle;

[0070] (6) The pH of the organic salt phase was adjusted to 4.8 using a 10 wt % hydrochloric acid solution, and then concentrated to a solid content of 20 wt % using a nanofiltration membrane with a molecular weight cutoff of 200 Da at a membrane pressure of 4.0 MPa to obtain a permeate solution 3 and a retentate solution 3; the retentate solution was thermally concentrated to a solid content of 45 wt %, and finally spray-dried to obtain 1038.0 g of scutellaria baicalensis flavonoids, wherein the total scutellaria baicalensis flavonoids content was 45.7 wt %, and the yield was 96.4%;

[0071] (7) using a reverse osmosis membrane to concentrate the solid content of the organic phase to 12 wt % to obtain a retentate 4 and a permeate 4; the retentate 4 was thermally concentrated to a solid content of 49 wt % and finally spray dried to obtain 4008 g of Scutellaria baicalensis polysaccharide with a solid content of 22.7 wt % and a yield of 98.2%; the permeate 4 was used as a mobile phase in the simulated moving bed chromatography separation of step (5);

[0072] (8) The permeate 2 of step (3) and the permeate 3 of step (6) are mixed and concentrated to a solid content of 7 wt % using a reverse osmosis membrane to obtain a retentate 5 and a permeate 5. The retentate 5 is thermally concentrated to a solid content of 69 wt %, then cooled to 38° C. for precipitation until no new precipitate is generated, and filtered to obtain KCl with a content of ≥ 90%. The permeate 5 is used as a mobile phase in the simulated moving bed chromatography separation of step (5).

[0073] Comparative Example 1

[0074] Compared with Example 1, the difference is that in step (1), the pH of the pretreatment liquid is 3.0, and the other conditions are the same as those in Example 1, and 891.2 g of scutellaria baicalensis flavonoids are obtained, with a content of 37.5 wt% and a yield of 67.9%; 3971 g of scutellaria baicalensis polysaccharides are obtained, with a content of 21.9 wt% and a yield of 93.9%.

[0075] Comparative Example 2

[0076] Compared with Example 1, the difference is that in step (1), the pH of the pretreatment liquid is 6.0, and the other conditions are the same as those in Example 1, and 901.3 g of scutellaria baicalensis flavonoids are obtained, with a content of 38.4 wt% and a yield of 70.3%; 4107 g of scutellaria baicalensis polysaccharides are obtained, with a content of 21.6 wt% and a yield of 95.7%.

[0077] Comparative Example 3

[0078] Compared with Example 1, the difference is that in step (2), the volume of the raw material is concentrated to 5%, and the other conditions are the same as those in Example 1, and 954.3 g of scutellaria baicalensis flavonoids are obtained, with a content of 45.1 wt% and a yield of 87.5%; 3907 g of scutellaria baicalensis polysaccharide are obtained, with a content of 22.5 wt% and a yield of 94.9%.

[0079] Comparative Example 4

[0080] Compared with Example 1, the difference is that in step (3), the solid content is concentrated to 10%, and the other conditions are the same as those in Example 1, and 1016.5g of Scutellaria baicalensis flavonoids are obtained, with a content of 43.2wt% and a yield of 89.3%; 4063g of Scutellaria baicalensis polysaccharide are obtained, with a content of 21.3wt% and a yield of 93.4%.

[0081] Comparative Example 5

[0082] Compared with Example 1, the difference is that in step (3), the solid content is concentrated to 30%, and the other conditions are the same as those in Example 1, and 1025.2 g of scutellaria baicalensis flavonoids are obtained, with a content of 41.8wt% and a yield of 87.1%; 3985 g of scutellaria baicalensis polysaccharides are obtained, with a content of 22.0wt% and a yield of 94.6%.

[0083] Comparative Example 6

[0084] Compared with Example 1, the difference is that in step (4), the pH of the liquid to be treated is 5.0, and the other conditions are the same as those in Example 1, and 763.2 g of scutellaria baicalensis flavonoids are obtained, with a content of 35.1 wt% and a yield of 54.4%; 4289 g of scutellaria baicalensis polysaccharides are obtained, with a content of 20.6 wt% and a yield of 95.4%.

[0085] Comparative Example 7

[0086] Compared with Example 1, the difference is that in step (4), the pH of the liquid to be treated is 7.5, and the other conditions are the same as those in Example 1, and 872.1 g of scutellaria baicalensis flavonoids are obtained, with a content of 20.4 wt% and a yield of 36.2%; 4221 g of scutellaria baicalensis polysaccharides are obtained, with a content of 21.1 wt% and a yield of 96.1%.

[0087] Comparative Example 8

[0088] Compared with Example 1, the difference is that in step (5), Zhejiang Zhengguang Industrial styrene-based cationic resin D331 is used to replace the Lanxiao Technology acrylic resin S2850 in the chromatographic column, and the other conditions are the same as those in Example 1, and 3018g of Scutellaria baicalensis flavonoids are obtained, with a content of 10.2wt% and a yield of 62.6%; 2016g of Scutellaria baicalensis polysaccharide, with a content of 14.5wt% and a yield of 31.5%.

[0089] Comparative Example 9

[0090] Compared with Example 1, the difference is that in step (5), the circulating liquid flushing volume is 40 v / v% of the volume of the single column chromatography column, and the other conditions are the same as those in Example 1, and 908.4 g of scutellaria flavonoids are obtained, with a content of 43.6 wt% and a yield of 80.5%; 4112 g of scutellaria polysaccharides are obtained, with a content of 22.0 wt% and a yield of 97.6%.

[0091] Comparative Example 10

[0092] Compared with Example 1, the difference is that in step (5), the circulating liquid flushing volume is 50 v / v% of the volume of the single column chromatography column, and the other conditions are the same as in Example 1, and 1085.1 g of Scutellaria baicalensis flavonoids are obtained, with a content of 39.5 wt% and a yield of 87.1%; 3921 g of Scutellaria baicalensis polysaccharides are obtained, with a content of 22.3 wt% and a yield of 94.4%.

[0093] Comparative Example 11

[0094] Compared with Example 1, the difference is that in step (5), the water flushing volume is 10 v / v% of the volume of the single column chromatography column, and the other conditions are the same as in Example 1, and 933.2 g of scutellaria baicalensis flavonoids are obtained, with a content of 42.6 wt% and a yield of 80.8%; 4071 g of scutellaria baicalensis polysaccharides are obtained, with a content of 22.3 wt% and a yield of 98.0%.

[0095] Comparative Example 12

[0096] Compared with Example 1, the difference is that in step (5), the water flushing volume is 20 v / v% of the volume of the single column chromatography column, and the other conditions are the same as in Example 1, and 1058.9 g of Scutellaria baicalensis flavonoids are obtained, with a content of 38.5 wt% and a yield of 82.9%; 3954 g of Scutellaria baicalensis polysaccharides are obtained, with a content of 21.9 wt% and a yield of 93.5%.

[0097] Comparative Example 13

[0098] Compared with Example 1, the difference is that in step (5), the amount of water analysis is 20 v / v% of the volume of the single column chromatography column, and the other conditions are the same as those in Example 1, and 1382.0 g of scutellaria baicalensis flavonoids are obtained, with a content of 31.7 wt% and a yield of 89.0%; 3637 g of scutellaria baicalensis polysaccharides are obtained, with a content of 21.8 wt% and a yield of 85.6%.

[0099] Comparative Example 14

[0100] Compared with Example 1, the difference is that in step (5), the feed amount of the liquid to be treated is 5 v / v% of the volume of the single column chromatography column, and the other conditions are the same as in Example 1, and 996.7 g of Scutellaria baicalensis flavonoids are obtained, with a content of 43.0 wt% and a yield of 87.1%; 4058 g of Scutellaria baicalensis polysaccharide are obtained, with a content of 22.1 wt% and a yield of 96.8%.

[0101] Comparative Example 15

[0102] Compared with Example 1, the difference is that in step (5), the feed amount of the liquid to be treated is 20 v / v% of the volume of the single column chromatography column, and the other conditions are the same as in Example 1, and 1120.0 g of Scutellaria baicalensis flavonoids are obtained, with a content of 36.5 wt% and a yield of 83.1%; 3915 g of Scutellaria baicalensis polysaccharide are obtained, with a content of 20.1 wt% and a yield of 84.9%.

[0103] Comparative Example 16

[0104] Compared with Example 1, the difference is that in step (5), based on the volume of the resin in a single chromatographic column, the circulating flushing flow rate is 1.0 BV / h, and the other conditions are the same as in Example 1; 1011.0 g of scutellaria flavonoids are obtained, with a content of 43.5 wt% and a yield of 89.4%; 4029 g of scutellaria polysaccharide are obtained, with a content of 22.4 wt% and a yield of 97.4%.

[0105] Comparative Example 17

[0106] Compared with Example 1, the difference is that in step (5), based on the volume of resin in a single chromatographic column, the circulating flushing flow rate is 3.0 BV / h, and the other conditions are the same as those in Example 1; 1108.2 g of scutellaria baicalensis flavonoids are obtained, with a content of 39.5 wt% and a yield of 89.0%; 3937 g of scutellaria baicalensis polysaccharides are obtained, with a content of 22.0 wt% and a yield of 93.5%.

[0107] Comparative Example 18

[0108] Compared with Example 1, the difference is that in step (5), the water flushing flow rate is 1.0 BV / h, and the other conditions are the same as those in Example 1, and 1032.7 g of Scutellaria baicalensis flavonoids are obtained, with a content of 43.9 wt% and a yield of 92.1%; 4017 g of Scutellaria baicalensis polysaccharides are obtained, with a content of 22.5 wt% and a yield of 97.5%.

[0109] Comparative Example 19

[0110] Compared with Example 1, the difference is that in step (5), the water flushing flow rate is 3.0 BV / h, and the other conditions are the same as those in Example 1, and 1099.4 g of Scutellaria baicalensis flavonoids are obtained, with a content of 40.8 wt% and a yield of 91.2%; 3945 g of Scutellaria baicalensis polysaccharides are obtained, with a content of 22.1 wt% and a yield of 94.1%.

[0111] Comparative Example 20

[0112] Compared with Example 1, the difference is that in step (6), the pH of the organic salt phase is adjusted to 6.0 with hydrochloric acid solution, and the other conditions are the same as those in Example 1, and 1068.5g of Scutellaria baicalensis flavonoids are obtained, with a content of 35.7wt% and a yield of 77.5%; 3986g of Scutellaria baicalensis polysaccharide are obtained, with a content of 22.6wt% and a yield of 97.2%.

[0113] In summary, the present invention uses scutellaria baicalensis acid precipitation waste liquid as raw material, first adopts membrane technology for preliminary separation, and then adopts a simulated moving bed chromatography separation system for secondary separation. After a series of treatments such as concentration and crystallization, scutellaria baicalensis polysaccharide and scutellaria baicalensis flavonoids products are respectively recovered, and a high-content potassium chloride product is obtained.

[0114] When the baicalin acid precipitation waste liquid is pretreated, the pH of the baicalin acid precipitation waste liquid needs to be reasonably adjusted before cooling to prevent the cooling and precipitation of scutellariae substances during the cooling process. Compared with Example 1, in Comparative Examples 1-2, the pH of the pretreatment liquid is too low or too high, and the yield and purity of scutellariae flavonoids and scutellariae polysaccharides are reduced to a certain extent, because when the pH is low, the scutellariae substances will precipitate after cooling, and some effective components will be lost, and when the pH is too high, during the membrane concentration process, the flavonoids are in contact with the air, and some effective components are destroyed. Therefore, in order to ensure the high yield and high purity of scutellariae flavonoids and scutellariae polysaccharides, the pH of the pretreatment liquid is controlled to be 4.0-5.0.

[0115] In order to remove impurities, macromolecular polysaccharides and proteins in the scutellaria acidification waste liquid, a ceramic membrane was used for filtration. Compared with Example 1, in Comparative Example 3, the ceramic membrane filtration concentration was insufficient, the yield of scutellaria flavonoids decreased significantly, and the purity and yield of scutellaria polysaccharides were also affected to a certain extent, mainly because the concentration was insufficient, and some scutellaria polysaccharides and scutellaria flavonoids remained in the retentate. Therefore, when using a nanofiltration membrane for concentration, it was concentrated to 2-3% of the original volume.

[0116] In order to remove potassium chloride and small molecule impurities, and to effectively control the solid content of the treated liquid to facilitate simulated moving bed chromatography separation, a nanofiltration membrane is used to treat the permeate 1, and the solid content of the retentate 2 needs to be reasonably adjusted during the treatment process. In Comparative Examples 4 and 5, the solid content of the retentate 2 is too low or too high, and the yield and purity of scutellaria baicalensis flavonoids and scutellaria baicalensis polysaccharides have a certain degree of purity reduction, because the solid content of the retentate 2 is too high, and part of the scutellaria baicalensis flavonoids and scutellaria baicalensis polysaccharides will enter the permeate 2, and if the solid content is too low, there will be impurities in the retentate 2, affecting the subsequent recovery of scutellaria baicalensis flavonoids and scutellaria baicalensis polysaccharides. Therefore, in order to ensure the high yield and high purity of scutellaria baicalensis flavonoids and scutellaria baicalensis polysaccharides, the solid content of the retentate 2 is controlled to be 15-25wt%.

[0117] When using a simulated moving bed chromatography separation system for separation, it is necessary to reasonably control the conditions, such as the pH of the liquid to be treated, feed amount, feed flow rate, circulating liquid flushing amount, circulating liquid flushing flow rate, water flushing amount, water flushing flow rate, etc. In Comparative Examples 6-19, the conditions were improperly controlled, and the purity and yield of Scutellaria baicalensis flavonoids and Scutellaria baicalensis polysaccharides were significantly reduced.

[0118] In Comparative Example 20, during the membrane concentration process for recovering scutellaria flavonoids, the pH was too high, and scutellaria substances were easily oxidized by oxygen in the air, resulting in product loss, and thus a decrease in the purity and yield of the product.

[0119] Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas, including the best mode, and also enable any technician in the field to practice the present invention, including making and using any device or system, and implementing any combined method. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements similar to the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, then these other embodiments should also be included in the scope of the claims.

Claims

1. A method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed, characterized in that: The following steps are involved: (1) adjusting the pH of the baicalin acid precipitation waste liquid to 4.0-5.0, cooling, and obtaining a pretreatment solution; (2) using a ceramic membrane to concentrate the pre-treated liquid to 2-3% of the original volume, and collecting the permeate; (3) concentrating the permeate 1 by a nanofiltration membrane to obtain a permeate 2 and a retentate 2 having a solid content of 15-25 wt %; (4) adjusting the pH of the retentate second to 6.0-6.5 to obtain a liquid to be treated; pumping the liquid to be treated into a simulated moving bed chromatography separation system, using an acrylic resin as a stationary phase and water as a mobile phase, for separation, and collecting an organic phase and an organic salt phase; (5) adjusting the pH of the organic salt phase to 4.5-5.0, filtering with a nanofiltration membrane, collecting the retentate three and the permeate three, and concentrating the retentate three by heat and spray drying to obtain scutellaria baicalensis flavonoids; (6) The organic phase is concentrated by a reverse osmosis membrane to obtain a retentate solution 4 and a permeate solution 4, and the retentate solution 4 is thermally concentrated and then spray-dried to obtain Scutellaria baicalensis polysaccharide; (7) The permeate 2 of step (3) and the permeate 3 of step (5) are combined and concentrated by reverse osmosis membrane to obtain retentate 5 and permeate 5. The retentate 5 is thermally concentrated and then cooled, and then filtered. The filter cake is dried to obtain potassium chloride.

2. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In step (2), the filtration pore size of the ceramic membrane is 5-10 nm, and the concentration pressure is 0.4-0.8 MPa.

3. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In step (3), the molecular weight cutoff of the nanofiltration membrane is 150-300 Da; and / or the membrane pressure during concentration is 3.0-5.0 MPa.

4. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In steps (1) and (4), when adjusting the pH, an alkaline solution with a concentration of 10-30 wt% is used for adjustment, and the alkaline solution is a mixture of one or more of potassium hydroxide, potassium bicarbonate, and potassium carbonate.

5. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In step (4), the average particle size of the acrylic resin is 350-450 μm; and / or the diameter-to-height ratio of the single-column chromatographic column of the simulated mobile chromatographic separation system is 1:2-3; And / or the simulated moving bed separation system includes eight chromatographic columns connected in series and end to end; a cyclic separation process includes cyclic flushing, water flushing, water analysis, and feeding process, the water analysis and feeding process are carried out simultaneously, and the organic salt phase is recovered in the water flushing process and the feeding process, and the organic phase is recovered in the water analysis process.

6. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 5, characterized in that: In step (4), during one circulation process, the flushing amount of the circulating liquid is 43-45 v / v% of the volume of the single column chromatographic column, the flushing amount of water is 15-17 v / v% of the volume of the single column chromatographic column, the water analysis amount is 30-35 v / v% of the volume of the single column chromatographic column, and the feed amount of the treated liquid is 10-12 v / v% of the volume of the single column chromatographic column.

7. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 5, characterized in that: In step (4), based on the volume of resin in a single chromatographic column, the circulating flushing flow rate is 1.5-2.0 BV / h, the water flushing flow rate is 1.5-2.0 BV / h, the water analysis flow rate is 1.5-2.0 BV / h, the feed flow rate is 0.5-0.7 BV / h, the circulating flushing time is 12.9-18.0 min, the water flushing time is 4.5-6.8 min, the water analysis time is 9.0-14.0 min, and then switch to the next cycle.

8. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In step (5), a hydrochloric acid solution with a concentration of 5-20wt% is used to adjust the pH of the organic salt phase, the molecular weight cutoff of the nanofiltration membrane is 150-300Da, the membrane pressure during filtration using the nanofiltration membrane is 3.0-5.0MPa, and the solid content of the retentate concentrated during filtration is 15-25wt%.

9. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In step (6), the organic phase is concentrated to a solid content of 10-20 wt% by reverse osmosis membrane; thermally concentrated to a solution solid content of 45-60 wt%; and / or the permeate is used as a mobile phase in the simulated moving bed chromatography separation process of step (4).

10. The method for treating scutellaria acidification waste liquid by using membrane technology and simulated moving bed according to claim 1, characterized in that: In step (7), the reverse osmosis membrane is concentrated to a solid content of 5-10wt%; and / or the permeate five is used as a mobile phase in the simulated moving bed chromatography separation process of step (4); and / or it is thermally concentrated to a solid content of 65-75wt%; and / or the temperature is lowered to 20-45°C for precipitation.