A method for cleaning cationic resin and its application

Abstract

The present invention relates to the technical field of resin cleaning, and specifically provides a method for cleaning a cationic resin and an application thereof. The present invention provides a method for cleaning a cationic resin, wherein a cleaning solution A and a cleaning solution B are used to clean the cationic resin; the cleaning solution A is an aqueous solution of a chelating agent; the chelating agent includes EDTA or its sodium salt and GLDA; the molar ratio of EDTA or its sodium salt to GLDA is (0.1-2):1; the cleaning solution B is a bacterial solution, and the bacteria in the bacterial solution include Leuconostoc and Pediococcus; the ratio of the number of live bacteria of Leuconostoc and Pediococcus is 1:(0.4-3.6). The method for cleaning a cationic resin provided by the present invention can effectively remove the heavy metals adsorbed by the resin without affecting its adsorption capacity.

Description

Technical Field

[0001] The invention relates to the technical field of resin cleaning, in particular to a method for cleaning a cationic resin and application thereof. Background Art

[0002] It is very important to remove potential heavy metal contaminants in food production and processing. In the prior art, chromatography is usually used to adsorb impurities such as heavy metals in solutions such as milk. However, the prior art rarely pays attention to how to clean and regenerate the resin filler in the chromatography column after the heavy metals are adsorbed.

[0003] Commonly used chromatography column cleaning methods include: (1) Solvent soaking method, using methanol, ethanol and other organic solvents to soak the chromatography column filler for a period of time to dissolve and remove contaminants. The soaking time depends on the degree of contamination and the effect of the solvent, usually several hours to overnight. (2) Pure water cleaning method, for some contaminants that are insoluble in organic solvents, pure water can be used for cleaning. Rinse the chromatography column filler with pure water several times until the effluent is clear and transparent. For chromatography column fillers that adsorb contaminants that are difficult to remove, weak acids or weak bases are usually used for cleaning; for fillers with protein residues, weak bases (such as NaOH) can be used for cleaning; for fillers with inorganic salt residues, weak acids (such as acetic acid) can be used for cleaning. In addition, in some cases, the filler can be cleaned with a solution containing a detergent. Select a suitable detergent and clean the filler according to its concentration and contact time. After cleaning, rinse it with a large amount of pure water and dry it with an appropriate solvent to complete the regeneration of the chromatography column.

[0004] However, for chromatographic column resin fillers that have adsorbed heavy metals, it is difficult to completely remove them through a simple elution process due to the strong binding force between the heavy metal ions and the fillers of the chromatographic column. In addition, in this case, strong acids, strong bases or other chemical reagents may be required to remove the heavy metals from the fillers, which not only increases the processing cost and has poor cleaning effects, but may also cause secondary pollution to the environment and reduce the service life of the resin. In particular, strong acids can cause the resin skeleton to dissolve, thereby destroying the structure and adsorption capacity of the resin, resulting in the filler being unable to be reused.

[0005] At present, the methods for removing heavy metals are mainly used in soil and water pollution, but the physical, chemical and structural properties of soil and water are very different from the resin fillers used in chromatography processes, and cannot be effectively converted. If the current chelating agent method is directly applied to the cleaning of heavy metals in the resin, not only the removal rate is low, but also the resin is damaged. Therefore, it is necessary to conduct further research on how to remove heavy metals in the resin. Summary of the invention

[0006] In order to make up for the defects of the prior art, the purpose of the present invention is to effectively remove heavy metals therein without affecting the regeneration adsorption capacity of the resin.

[0007] In a first aspect, the present invention provides a method for cleaning a cationic resin, wherein the cationic resin is cleaned using a cleaning solution A and a cleaning solution B; the cleaning solution A is an aqueous solution of a chelating agent; the chelating agent includes EDTA or its sodium salt and GLDA; the molar ratio of EDTA or its sodium salt to GLDA is (0.1-2):1; the cleaning solution B is a bacterial solution, wherein the bacteria in the bacterial solution include Leuconostoc and Pediococcus; the ratio of the number of live bacteria of Leuconostoc to Pediococcus is 1:(0.4-3.6).

[0008] The present invention has found that although EDTA or its sodium salt and GLDA are both known metal chelators, when they are used alone in resin cleaning, they cannot achieve an ideal heavy metal removal effect. After repeated studies, the present invention finally found that when EDTA or its sodium salt and GLDA are first used in combination in a specific ratio and then combined with a specific combined bacterial agent for cleaning, the heavy metals in the resin can be effectively removed without affecting the adsorption regeneration ability of the resin. The cleaned resin can continue to function as a filler for the chromatography column, saving the cost of the chromatography process.

[0009] In addition, the present invention has also found that after the cationic resin adsorbs the positively charged target substance, after desorption with a conventional eluent, a small amount of positively charged substances that cannot be completely washed away will still remain in the resin. The cleaning method of the present invention can effectively remove the positively charged substances remaining in the resin, effectively regenerate the adsorption capacity of the resin, and ensure that the resin does not cause pollution to subsequent operations when it is used again.

[0010] The cationic resin in the present invention is a product known in the art, which can exchange with cations (positively charged ions) in the solution. Cationic resins are generally composed of a polymer matrix and functional ionic groups, which can bind to cations to achieve the removal or recovery of cations in the solution. The type of functional ionic groups in the cationic resin of the present invention is not limited, as long as the function of binding to cations can be achieved.

[0011] EDTA or its sodium salt refers to EDTA, EDTA-2Na, and EDTA-4Na.

[0012] Heavy metals in the present invention generally refer to metals with a density greater than 4.5 g / cm 3 Metal elements with stable chemical properties, not easy to degrade, and can accumulate in organisms through the food chain usually include copper, lead, zinc, tin, nickel, cobalt, antimony, mercury, cadmium and bismuth.

[0013] In the method for cleaning cationic resin provided by the present invention, the Leuconostoc is Leuconostoc citrinum or Leuconostoc mesenteroides; and the Pediococcus is Pediococcus perenne.

[0014] In the method for cleaning cationic resin provided by the present invention, the bacterial liquid is an aqueous solution of an organic acid or an organic acid salt of the bacteria; the organic acid is one or more of citric acid, lactic acid, malic acid, acetic acid, and tartaric acid; the organic acid salt is one or more of the sodium salt or potassium salt of the organic acid; the pH of the bacterial liquid is 5-6.5. Preferably, the bacterial liquid is an aqueous solution of sodium acetate, sodium citrate, citric acid, or tartaric acid of the bacteria.

[0015] The present invention uses a solution containing an organic acid to prepare the bacterial solution, which can provide a carbon source for the microorganisms, which is beneficial to maintaining the physiological activity of the microorganisms; it can also adjust the pH in the bacterial solution, so that more negatively charged groups are exposed on the surface of the microorganisms, which is helpful for the adsorption of heavy metals and uneluted cationic substances.

[0016] In the method for cleaning cationic resin provided by the present invention, the total concentration of the chelating agent in the cleaning solution A is 0.008-0.29 mol / L, and the pH of the cleaning solution A is 7.5-9; the total concentration of the bacteria in the cleaning solution B is 5×10 7 -2×10 9 CFU / mL.

[0017] The concentration of components in the cleaning solution of the present invention can be used to achieve both treatment efficiency and effect.

[0018] In the method for cleaning a cationic resin provided by the present invention, the cleaning liquid A and the cleaning liquid B are used to clean the cationic resin in the following manner:

[0019] The cationic resin is mixed with cleaning solution A, and stirred for 1.5-3.5 hours for the first cleaning, and then the cationic resin that has been cleaned for the first time is mixed with cleaning solution B, and stirred for 30-60 minutes for the second cleaning;

[0020] During the first cleaning, the volume of the cleaning solution A is 3-5 times the volume of the cationic resin;

[0021] During the second cleaning, the volume of the cleaning solution B is 2-4 times the volume of the cationic resin that has been cleaned for the first time;

[0022] The stirring speed during the first cleaning and the second cleaning is 180-300 rpm.

[0023] In the method for cleaning a cationic resin provided by the present invention, when the cationic resin is loaded in a chromatography column, the cationic resin is cleaned by using cleaning solution A and cleaning solution B as follows:

[0024] The cleaning solution A is injected into the chromatography column, and the volume of the cleaning solution A is 4-7 times the volume of the cationic resin; the total time for the cleaning solution A to flow through the cationic resin as a whole is 700-1100s; then the cleaning solution B is injected into the chromatography column, and the volume of the cleaning solution B is 1.5-4 times the volume of the cationic resin; the total time for the cleaning solution B to flow through the cationic resin as a whole is 180-230s.

[0025] In the method for cleaning cationic resin provided by the present invention, the temperature of the cleaning solution A is 45-55°C; the temperature of the cleaning solution B is 25-35°C.

[0026] The present invention preferably uses a dynamic washing method to clean the resin. Those skilled in the art can control the washing method, washing time and the amount of the washing solution based on the principle that the resin is fully contacted with the cleaning solution and is effectively washed. The application of the above two washing methods of the present invention is conducive to taking into account both the washing effect and the washing efficiency. When cleaning the cationic resin in the chromatography column, the selection of the cleaning solution injection flow rate can be carried out according to the common sense in the art, according to the chromatography column volume and the total amount of the cleaning solution set by the present invention and the total time flowing through the resin.

[0027] In the method for cleaning the cationic resin provided by the present invention, after the cationic resin is cleaned with cleaning solution A and cleaning solution B, the method further comprises the step of washing the cationic resin with water.

[0028] The present invention can remove the cleaning liquid remaining in the resin after cleaning by water washing. Under the premise of ensuring that the cleaning is clean and the resin structure is not damaged, those skilled in the art can adopt the water washing method known in the art.

[0029] In a second aspect, the present invention provides a cationic resin cleaning solution, which includes a cleaning solution A and a cleaning solution B; the cleaning solution A and the cleaning solution B are as described above.

[0030] The cleaning liquid of the present invention can clean the cationic resin after adsorption and desorption, or the unused cationic resin, and completely remove the heavy metals that may be contained in the resin and the cationic substances that have not been desorbed.

[0031] In a third aspect, the present invention provides the use of the above-mentioned method for cleaning a cationic resin in removing heavy metals in a cationic resin or regenerating a chromatography column filled with a cationic resin.

[0032] The method for cleaning the cationic resin of the present invention can be used to clean and regenerate the used chromatography column after the chromatography experiment. At the same time, it is not ruled out that there is heavy metal contamination in the preparation process of the chromatography column. In order to avoid the chromatography column from contaminating the sample, the chromatography column can also be cleaned by the method of the present invention before chromatography.

[0033] Specifically, during the chromatography experiment, after the components in the liquid sample are separated by chromatography, the heavy metals and / or undesorbed substances in the liquid sample will be adsorbed and remain in the resin filler. The method provided by the present invention can be used to clean the resin in the chromatography column used, so that the resin filler can be reused to avoid contamination during subsequent resin applications.

[0034] The liquid sample is a liquid sample that can be purified by using a cation exchange resin and may carry heavy metal ions, such as biological products, dairy products, etc.

[0035] In a fourth aspect, the present invention provides a method for removing heavy metals from a product, comprising: using a chromatography column to adsorb the heavy metals in the product, and then using the above method to remove the heavy metals in the filler of the chromatography column; the filler is a cationic resin.

[0036] As a specific implementation, the target substance and heavy metals in the liquid sample of the product can be adsorbed on the resin filler of the chromatography column, and the liquid sample in the chromatography column can be drained using a buffer solution or sterile water. After that, the target substance is eluted using a desorption solution, and then the above-mentioned method for cleaning the cationic resin is used to remove the heavy metals and other residual cationic substances in the resin filler, thereby obtaining a product with heavy metals removed and a cleaned and regenerated resin (which can continue to be used to adsorb components in the liquid sample).

[0037] The beneficial effects of the present invention are:

[0038] According to the characteristics and application requirements of the cationic resin material, the present invention uses a specific chelating agent and a microbial adsorption method to effectively remove heavy metals in the resin and / or cationic substances remaining after desorption while maintaining the adsorption capacity of the resin. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are 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.

[0040] In the present invention, GLDA: glutamic acid-N,N-diacetic acid; EDTA: ethylenediaminetetraacetic acid.

[0041] The microorganisms used in the present invention are microorganisms of the genus Leuconostoc and Pediococcus. Considering that the genome information of microorganisms of the same genus is basically the same, all microorganisms of the genus Leuconostoc and Pediococcus can achieve the adsorption effect.

[0042] In a specific embodiment of the present invention, the Leuconostoc microorganism used is Leuconostoc citrinum Leuconostoc citreum CGMCC 1.14 and Leuconostoc mesenteroides Leuconostoc mesenteroides CGMCC 1.578; the Pediococcus microorganism used was Pediococcus perenne Pediococcus lolii CGMCC 1.528. The strains used in the specific embodiments of the present invention can be purchased from the China General Microbiological Culture Collection Center.

[0043] For the detection method of heavy metals, please refer to GB5009.268.

[0044] Example 1

[0045] This embodiment provides a method for cleaning a resin filler, which is as follows:

[0046] 1. Obtaining the cationic resin filler to be cleaned:

[0047] (1) The broken plant cell suspension was centrifuged at 5000 rpm for 5 min, the precipitate was discarded, and the supernatant was obtained. The contents of the target separation substance (alkaloid) and heavy metals in the supernatant were detected respectively.

[0048] The detection method for alkaloids is: GB / T 38571-2020.

[0049] In this embodiment, the content of heavy metals in the supernatant to be chromatographed is: 33.5 μg / L; zinc: 31.3 μg / L; copper: 47.3 μg / L; lead: 47.1 μg / L; chromium: 35.4 μg / L; mercury: 33.9 μg / L; arsenic: 41.4 μg / L; cadmium: 50.8 μg / L.

[0050] (2) Injection adsorption: Inject 20L of supernatant into a chromatography column (filler resin matrix is ​​6% cross-linked agarose, ligand is methanesulfonate, particle size is 100-300μm, filler volume is 106ml) at a rate of 106ml / min, collect the flow-through liquid, and detect the content of the target separation substance and each heavy metal in the flow-through liquid. Then calculate the adsorption rate of the target separation substance and heavy metal respectively.

[0051] The calculation formula of adsorption rate is (1-a / b) × 100%. a is the mass of target separation substance / heavy metal in the flow-through liquid, and b is the mass of target separation substance / heavy metal in the supernatant.

[0052] In this embodiment, the adsorption rate of the target separation substance is 95.93%, and the total adsorption rate of heavy metals is 100%.

[0053] (3) Desorption: Use sterile water to drain the raw material liquid in the chromatography column, then use 10CV of 0.65mol / L ammonia water as the eluent, and inject it into the chromatography column at a rate of 25ml / min to desorb the target separation substance to obtain the eluent. Detect the content of the target separation substance and each heavy metal in the eluent. Then calculate the elution rate of the target separation substance and heavy metal respectively. The calculation formula of the elution rate is c / (ba)×100%. a is the mass of the target separation substance / heavy metal in the flow-through liquid, b is the mass of the target separation substance / heavy metal in the supernatant, and c is the mass of the target separation substance / heavy metal in the eluent.

[0054] In this embodiment, the elution rate of the target separation substance is 89.87%, and the total elution rate of heavy metals is 0.15%, indicating that heavy metals and part of the target separation substance are retained in the chromatography column resin.

[0055] 2. Cleaning of cationic resin filler:

[0056] (1) Preparation of cleaning solution A: Prepare a chelating agent aqueous solution, wherein the total concentration of the chelating agent is 0.008 mol / L, and the molar ratio of GLDA to EDTA-2Na in the chelating agent is 1:2; the pH value of the cleaning solution A is 8.5.

[0057] (2) Prepare cleaning solution B: Use sodium acetate solution to prepare a bacterial solution with a pH value of 5, including a live bacterial count ratio of 1:2.5. Leuconostoc citreum CGMCC 1.14 and Pediococcus lolii CGMCC 1.528, total viable count 2×10 9 CFU / mL.

[0058] (3) CIP-cleaning: 4CV (4 times the volume of the cationic resin) of cleaning solution A was injected into the column at an injection temperature of 50°C. The total time for all cleaning solution A to flow through the cationic resin in the column was 1000 s. 3CV of cleaning solution B was injected into the column at an injection temperature of 25°C. The total time for all cleaning solution B to flow through the cationic resin in the column was 225 s.

[0059] (4) Water washing: Use deionized water to rinse the remaining cleaning solution in the chromatography column until no new substances are washed out.

[0060] (5) Storage: Inject 2CV of a solution containing 0.2M sodium acetate and 20% ethanol into the chromatography column. The total time for all the solution to flow through the cationic resin in the chromatography column is 240 s.

[0061] 3. Effect evaluation:

[0062] (1) The sum of the contents of the target separation substance in the flow-through liquid of step (2) of step 1, the eluate of step (3), the cleaning liquid A after cleaning the chromatographic column in step (3) of step 2, and the cleaning liquid B was detected and calculated, and compared with the content of the target separation substance in the supernatant before the injection adsorption in step 1. It was found that the two were basically the same, indicating that after the resin was cleaned with the cleaning liquid of the present invention, there was basically no target separation substance left in the resin.

[0063] The content of each heavy metal in the resin of the chromatography column after cleaning in step 2 was detected. As a result, none of the heavy metals were detected, indicating that the cleaning method of the present invention can effectively clean the cationic resin.

[0064] (2) The resin cleaned in step 2 was used as the filler of the chromatography column, and the same supernatant was chromatographed according to the method in step 1, and then the adsorption rates of the target separated substances and heavy metals were calculated respectively. The adsorption rate of the cationic resin for the target separated substances after the final cleaning was 95.6%. The total adsorption rate of heavy metals was 99.56%. This indicates that the cleaning method of the present invention has little effect on the adsorption rate of the resin.

[0065] Example 2

[0066] This embodiment provides a method for cleaning a resin filler, which is as follows:

[0067] 1. Obtaining the cationic resin filler to be cleaned:

[0068] (1) Prepare skim milk (fat content: 0.15%) containing heavy metal standards (lead: 50 μg / L; chromium: 100 μg / L; mercury: 50 μg / L; arsenic: 50 μg / L; cadmium: 50 μg / L). The content of the target separation substance (alkaline protein) was 27.5%.

[0069] For the detection method of basic protein, please refer to Chinese patent CN 117949566 A.

[0070] (2) Sample injection and adsorption: The sample was loaded into a chromatography column (filler resin matrix was 6% cross-linked agarose, ligand was sulfopropyl, particle size was 100-300 μm, filler volume was 30 ml) at a flow rate of 30 ml / min, the sample volume was 5 L, the flow-through liquid was collected, and the content of the target separation substance and each heavy metal in the flow-through liquid was detected respectively. Then, the adsorption rate of the target separation substance and heavy metal was calculated respectively (the calculation method was the same as that in Example 1).

[0071] In this embodiment, the adsorption rate of the target separation substance is 94.56%, and the total adsorption rate of heavy metals is 100%.

[0072] (3) Desorption: After balancing the chromatography column with deionized water, the target substance was eluted with 2M NaCl solution, the eluent injection volume was 15CV, and the flow rate was 7.5ml / min; the eluent was collected, and the content of the target substance and each heavy metal in the eluent was detected. Then, the elution rate of the target substance and heavy metal was calculated respectively (the calculation method was the same as that in Example 1).

[0073] In this embodiment, the elution rate of the target separation substance is 92.71%, and the total elution rate of heavy metals is 0.39%, indicating that heavy metals and part of the target separation substance are retained in the chromatography column resin.

[0074] 2. Cleaning of cationic resin filler:

[0075] (1) Preparation of cleaning solution A: Prepare a chelating agent aqueous solution, wherein the total concentration of the chelating agent is 0.29 mol / L, and the molar ratio of GLDA to EDTA in the chelating agent is 1:0.1; the pH value of the cleaning solution A is 7.5.

[0076] (2) Prepare cleaning solution B: Use citric acid solution to prepare a bacterial solution with a pH value of 6.0, including a live bacterial count ratio of 1:3.6. Leuconostoc citreum CGMCC 1.14 and Pediococcus lolii CGMCC 1.528, total viable count 5×10 7 CFU / mL.

[0077] (3) CIP-cleaning: 7CV of cleaning solution A was injected into the column at an injection temperature of 48°C. The total time for all cleaning solution A to flow through the cationic resin in the column was 700 s. 2CV of cleaning solution B was injected into the column at an injection temperature of 35°C. The total time for all cleaning solution B to flow through the cationic resin in the column was 190 s.

[0078] (4) Water washing: Use deionized water to rinse the remaining cleaning solution in the chromatography column until no new substances are washed out.

[0079] (5) Storage: Inject 2CV of a solution containing 0.2M sodium acetate and 20% ethanol into the chromatography column. The total time for all the solution to flow through the cationic resin in the chromatography column is 240 s.

[0080] 3. Effect evaluation:

[0081] (1) The sum of the contents of the target separation substance in the flow-through liquid of step (2) of step 1, the eluent of step (3), the cleaning liquid A after cleaning the chromatographic column in step (3) of step 2, and the cleaning liquid B was detected and calculated, and compared with the content of the target separation substance in the spiked skim milk before the injection adsorption in step 1. It was found that the two were basically the same, indicating that after the resin was cleaned with the cleaning liquid of the present invention, there was basically no target separation substance left in the resin.

[0082] The content of each heavy metal in the resin of the chromatography column after cleaning in step 2 was detected. As a result, none of the heavy metals were detected, indicating that the cleaning method of the present invention can effectively clean the cationic resin.

[0083] (2) The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1, and then the adsorption rates of the target separated substances and heavy metals were calculated respectively. The adsorption rate of the cationic resin for the target separated substances after the final cleaning was 93.95%. The total adsorption rate of heavy metals was 100%. This indicates that the cleaning method of the present invention has little effect on the adsorption rate of the resin.

[0084] Experimental Example 3

[0085] This embodiment provides a method for cleaning a resin filler, which is as follows:

[0086] 1. Obtaining the cationic resin filler to be cleaned:

[0087] (1) Preparation of trehalose: Dissolve starch milk in water at 55°C to obtain a solution with a starch milk concentration of 10%. Adjust the pH to 6.2 to obtain gelatinized starch. Add α-amylase to the gelatinized starch and heat to 85°C. Keep the temperature for 25 min and cool to 60°C. Then add saccharifying enzyme for 2 h and adjust the pH to 5.0. Add maltooligosaccharide trehalose synthase, maltooligosaccharide trehalose hydrolase and trehalose synthase for enzymatic conversion for 12 h. Centrifuge at 4000 rpm for 10 min and collect the supernatant (trehalose-containing solution).

[0088] Prepare a trehalose solution containing heavy metal standards (lead: 100μg / L; chromium: 400μg / L; mercury: 100μg / L; arsenic: 100μg / L; cadmium: 100μg / L); detect the content of the target separation substance (trehalose). The test method for trehalose content is GB / T 23529-2009.

[0089] (2) Sample injection and adsorption: The sample was loaded into a chromatography column (filler resin matrix was 6% cross-linked agarose, ligand was carboxymethyl, particle size was 45-165 μm, filler volume was 21 ml) at a flow rate of 21 ml / min, the sample volume was 5 L, the flow-through liquid was collected, and the contents of the target separation substance (trehalose) and each heavy metal in the flow-through liquid were detected respectively. Then, the adsorption rates of the target separation substance and heavy metals were calculated respectively (the calculation method was the same as in Example 1).

[0090] In this embodiment, the adsorption rate of the target separation substance trehalose is 97.54%, and the total adsorption rate of heavy metals is 100%.

[0091] (3) Desorption: After balancing the chromatography column with deionized water, the target substance was eluted with 2M NaCl solution, the eluent injection volume was 10CV, and the flow rate was 5.3ml / min; the eluent was collected, and the content of the target substance and each heavy metal in the eluent was detected. Then, the elution rate of the target substance and heavy metal was calculated respectively (the calculation method was the same as that in Example 1).

[0092] In this example, the elution rate of the target separation substance trehalose was 97.30%, and the total elution rate of heavy metals was 0.58%, indicating that heavy metals and part of the target separation substance were retained in the chromatography column resin.

[0093] Cleaning of cationic resin filler:

[0094] (1) Preparation of cleaning solution A: Prepare a chelating agent aqueous solution, wherein the total concentration of the chelating agent is 0.15 mol / L, and the molar ratio of GLDA to EDTA in the chelating agent is 1:0.9; the pH value of the cleaning solution A is 9.

[0095] (2) Prepare cleaning solution B: Use sodium citrate solution to prepare a bacterial solution with a pH value of 6.5, including a live bacterial count ratio of 1:0.4. Leuconostoc citreum CGMCC 1.14 and Pediococcus lolii CGMCC 1.528, total viable count 1.5×10 8 CFU / mL.

[0096] (3) CIP-cleaning: 6.5 CV of cleaning solution A was injected into the column at an injection temperature of 45°C. The total time for all cleaning solution A to flow through the cationic resin in the column was 780 s. 1.5 CV of cleaning solution B was injected into the column at an injection temperature of 30°C. The total time for all cleaning solution B to flow through the cationic resin in the column was 180 s.

[0097] (4) Water washing: Use deionized water to rinse the remaining cleaning solution in the chromatography column until no new substances are washed out.

[0098] (5) Storage: Inject 1.5 CV of a solution containing 0.2 M sodium acetate and 20% ethanol into the chromatography column. The total time for all the solution to flow through the cationic resin in the chromatography column is 240 s.

[0099] 3. Effect evaluation:

[0100] (1) The sum of the contents of the target separation substance in the flow-through liquid of step (2) of step 1, the eluate of step (3), the cleaning liquid A after cleaning the chromatographic column in step (3) of step 2, and the cleaning liquid B was detected and calculated, and compared with the content of the target separation substance in the spiked trehalose-containing solution before injection adsorption in step 1. It was found that the two were basically the same, indicating that after cleaning the resin with the cleaning liquid of the present invention, there was basically no target separation substance left in the resin.

[0101] The content of each heavy metal in the resin of the chromatography column after cleaning in step 2 was detected. As a result, none of the heavy metals were detected, indicating that the cleaning method of the present invention can effectively clean the cationic resin.

[0102] (2) The resin cleaned in step 2 was used as the filler of the chromatography column, and the same solution spiked with trehalose was chromatographed according to the method in step 1, and then the adsorption rates of the target separated substance and heavy metals were calculated respectively. The adsorption rate of the cationic resin for the target separated substance after the final cleaning was 97.17%. The total adsorption rate of heavy metals was 99.15%. This indicates that the cleaning method of the present invention has little effect on the adsorption rate of the resin.

[0103] Example 4

[0104] This embodiment provides a method for cleaning a resin filler, which is as follows:

[0105] 1. Obtaining the cationic resin filler to be cleaned:

[0106] (1) Preparation of cell fermentation broth: Activated Corynebacterium glutamicum (ATCC 13032) was inoculated into 200 ml of liquid culture medium (2.5% hydrolyzed sugar, 0.5% urea, 0.04% magnesium sulfate, 0.15% potassium dihydrogen phosphate, 2.5% corn steep liquor, pH 7.0), and cultured at 32°C and 200 rpm for 12 h as seed liquid; the seed liquid from the previous step was inoculated into 2 L of liquid fermentation medium (0.2% cane molasses, 0.15% corn steep liquor, 0.04% magnesium sulfate, 0.17% Na2HPO4, 0.12% KCl, pH 7) at an inoculum rate of 2% (V / V), and fermented at 32°C and 200 rpm for 48 h. The culture was centrifuged at 6000 rpm for 5 min, the cells were removed, and the supernatant (fermentation broth) was collected.

[0107] Heavy metals were added to the fermentation broth prepared by the above method to prepare a fermentation broth containing heavy metal standards (lead: 70 μg / L; chromium: 130 μg / L; mercury: 70 μg / L; arsenic: 70 μg / L; cadmium: 70 μg / L), and the content of the target separation substance (glutamic acid) was detected. The detection method for the target separation substance is: GB5009.43-2016.

[0108] (2) Injection adsorption: 10L of supernatant was injected into a chromatography column (filler resin matrix was 6% cross-linked agarose, ligand was methanesulfonate, particle size was 100-300 μm, filler volume was 96 ml) at a rate of 96 ml / min, the flow-through liquid was collected, and the contents of the target separation substance and each heavy metal in the flow-through liquid were detected respectively. Then, the adsorption rates of the target separation substance and heavy metals were calculated respectively (the calculation method was the same as in Example 1).

[0109] In this embodiment, the adsorption rate of the target separation substance is 96.01%, and the total adsorption rate of heavy metals is 100%.

[0110] (3) Desorption: Use sterile water to drain the raw material liquid in the chromatography column, then use 15CV of 1 mol / L ammonia water as eluent, inject it into the chromatography column at a rate of 20 ml / min to desorb the target separation substance, and obtain an eluent. Detect the content of the target separation substance and each heavy metal in the eluent. Then calculate the elution rate of the target separation substance and heavy metal respectively (the calculation method is the same as that in Example 1).

[0111] In this embodiment, the elution rate of the target separation substance is 93.09%, and the total elution rate of heavy metals is 0.41%, indicating that heavy metals and part of the target separation substance are retained in the chromatography column resin.

[0112] 2. Cleaning of cationic resin filler:

[0113] (1) Preparation of cleaning solution A: Prepare a chelating agent aqueous solution, wherein the total concentration of the chelating agent is 0.23 mol / L, and the molar ratio of GLDA to EDTA-4Na in the chelating agent is 1:1.5; the pH value of the cleaning solution A is 8.

[0114] (2) Prepare cleaning solution B: Use tartaric acid solution to prepare a bacterial solution with a pH value of 5.5, including a live bacterial count ratio of 1:2. Leuconostoc mesenteroides CGMCC 1.578 and Pediococcus lolii CGMCC 1.528, total viable count 5×10 8 CFU / mL.

[0115] (3) CIP-cleaning: 5.5 CV of cleaning solution A was injected into the column at an injection temperature of 55 °C. The total time for all cleaning solution A to flow through the cationic resin in the column was 1100 s. 4 CV of cleaning solution B was injected into the column at an injection temperature of 27 °C. The total time for all cleaning solution B to flow through the cationic resin in the column was 200 s.

[0116] (4) Water washing: Use deionized water to rinse the remaining cleaning solution in the chromatography column until no new substances are washed out.

[0117] (5) Storage: Inject 2CV of a solution containing 0.2M sodium acetate and 20% ethanol into the chromatography column. The total time for all the solution to flow through the cationic resin in the chromatography column is 240 s.

[0118] 3. Effect evaluation:

[0119] (1) The sum of the contents of the target separation substance in the flow-through liquid of step (2) of step 1, the eluate of step (3), the cleaning liquid A after cleaning the chromatography column in step (3) of step 2, and the cleaning liquid B was detected and calculated, and compared with the content of the target separation substance in the spiked fermentation broth before injection and adsorption in step 1. It was found that the two were basically the same, indicating that after cleaning the resin with the cleaning liquid of the present invention, there was basically no target separation substance left in the resin.

[0120] The content of each heavy metal in the resin of the chromatography column after cleaning in step 2 was detected. As a result, none of the heavy metals were detected, indicating that the cleaning method of the present invention can effectively clean the cationic resin.

[0121] (2) The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked fermentation broth was chromatographed according to the method in step 1, and then the adsorption rates of the target separated substances and heavy metals were calculated respectively. The adsorption rate of the cationic resin for the target separated substances after the final cleaning was 95.26%. The total adsorption rate of heavy metals was 99.79%. It was shown that the cleaning method of the present invention did not substantially affect the adsorption rate of the resin.

[0122] Example 5

[0123] This embodiment provides a resin cleaning method, which is as follows:

[0124] 1. Obtaining the cationic resin to be cleaned:

[0125] (1) A heavy metal standard solution (lead: 100 μg / L; chromium: 400 μg / L; mercury: 100 μg / L; arsenic: 100 μg / L; cadmium: 100 μg / L) prepared with deionized water was mixed evenly with a cationic resin (resin matrix: 6% cross-linked agarose, ligand: methanesulfonate, particle size: 100-300 μm) at a volume ratio of 5:1, adsorbed at 180 rpm for 10 h, centrifuged at 4000 rpm for 10 min, the precipitate and supernatant were collected, and the content of each heavy metal in the supernatant was detected; in this example, the content of each heavy metal in the supernatant was not detected, indicating that the adsorption rate of the resin for heavy metals was 100%;

[0126] (2) Desorption: Add sterile water twice the volume of the cationic resin to the precipitate obtained in step (1) (the cationic resin adsorbing heavy metals), shake it at 180 rpm for 10 min, centrifuge it at 4000 rpm for 10 min, and collect the precipitate; then add the precipitate to a 2M NaCl solution three times the volume of the cationic resin, shake it at 180 rpm for 10 min, centrifuge it at 4000 rpm for 10 min, collect the supernatant (eluent) and the precipitate; detect the content of each heavy metal in the eluent. Then calculate the heavy metal elution rate. The elution rate is calculated as follows: the mass of heavy metal in the eluent / (the mass of heavy metal in the heavy metal standard solution - the mass of heavy metal in the supernatant obtained in step 1 (1)) × 100%.

[0127] In this embodiment, the total elution rate of heavy metals is 0.23%, indicating that heavy metals are retained in the resin.

[0128] 2. Cleaning of cationic resin

[0129] (1) Preparation of cleaning solution A: Prepare a chelating agent aqueous solution, wherein the total concentration of the chelating agent is 0.13 mol / L, and the molar ratio of GLDA to EDTA in the chelating agent is 1:1.2; the pH value of the cleaning solution A is 9.

[0130] (2) Prepare cleaning solution B: Use citric acid solution to prepare a bacterial solution with a pH value of 5, including a live bacterial count ratio of 1:1.5. Leuconostoc mesenteroides CGMCC 1.578 and Pediococcus lolii CGMCC 1.528, total viable count 7.5×10 8 CFU / mL.

[0131] (3) CIP-cleaning: Mix 4 times the volume of the resin with the cleaning solution A and the cationic resin, shake and stir thoroughly at 250 rpm for 2.5 hours. The temperature of the cleaning solution A is 50°C. Centrifuge at 4000 rpm for 10 minutes. Collect the supernatant A and the precipitate. Then mix 2.5 times the volume of the resin with the cleaning solution B and the precipitate (the cationic resin after cleaning with the cleaning solution A). Shake and stir thoroughly at 180 rpm for 45 minutes. The temperature of the cleaning solution B is 30°C. Centrifuge at 4000 rpm for 10 minutes. Collect the supernatant B and the precipitate.

[0132] (4) Washing: Add sterile water twice the volume of the cationic resin to the precipitate obtained in step (3) (the cationic resin after washing with washing solution B), shake and stir thoroughly at 180 rpm for 10 min, centrifuge at 4000 rpm for 10 min, collect the precipitate, and remove the remaining washing solution in the cationic resin until no new substances are washed out.

[0133] (5) Storage: Mix the precipitate obtained in step (4) with a solution containing 0.2 M sodium acetate and 20% ethanol in an amount twice the volume of the cationic resin, and stir the mixture at 180 rpm for 20 min to mix well.

[0134] 3. Effect evaluation:

[0135] (1) The content of each heavy metal in the cationic resin after cleaning with cleaning solution B in step 2 was detected. As a result, none of the heavy metals were detected, indicating that the cleaning method of the present invention can effectively clean the cationic resin.

[0136] (2) The cationic resin cleaned in step 2 was used as an adsorption material, and the same standard sample was adsorbed according to the method in step 1, and then the heavy metal adsorption rate was calculated. The total adsorption rate of heavy metals was 99.37%. This shows that the cleaning method of the present invention has little effect on the adsorption rate of the resin.

[0137] Comparative Example 1

[0138] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2. The cleaning method is as follows:

[0139] CIP-cleaning: The column was cleaned with 2 CV of 1 mol / L sodium hydroxide solution; the total time for all the sodium hydroxide solution to flow through the cationic resin in the column was 420 s. Afterwards, the column was washed with water and stored according to the method of Example 2.

[0140] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 47.41μg / L; chromium: 87.58μg / L; mercury: 49.91μg / L; arsenic: 39.63μg / L; cadmium: 47.52μg / L; the content of the target separation substance was 31.95%.

[0141] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 65.41%. The total adsorption rate of heavy metals was 37.39%.

[0142] Comparative Example 2

[0143] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total concentration of the chelating agent in the cleaning solution A remains unchanged, but only GLDA is used as the chelating agent component, and EDTA is not added.

[0144] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 40.03μg / L; chromium: 76.02μg / L; mercury: 39.67μg / L; arsenic: 26.78μg / L; cadmium: 35.73μg / L; the content of the target separation substance was 14.1%.

[0145] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 82.15%. The total adsorption rate of heavy metals was 75.62%.

[0146] Comparative Example 3

[0147] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total concentration of the chelating agent in the cleaning solution A remains unchanged, but only EDTA is used as the chelating agent component, and GLDA is not added.

[0148] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 37.21μg / L; chromium: 77.4μg / L; mercury: 37.15μg / L; arsenic: 27.31μg / L; cadmium: 39.61μg / L; the content of the target separation substance was 12.99%.

[0149] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 83.01%. The total adsorption rate of heavy metals was 77.94%.

[0150] Comparative Example 4

[0151] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that GLDA in the cleaning solution A is replaced by IDS.

[0152] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 30.26μg / L; chromium: 65.51μg / L; mercury: 35.85μg / L; arsenic: 23.14μg / L; cadmium: 31.43μg / L; the content of the target separation substance was 10.7%.

[0153] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 86.33%. The total adsorption rate of heavy metals was 82.98%.

[0154] Comparative Example 5

[0155] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total concentration of the chelating agent in the cleaning solution A remains unchanged, but the molar ratio of GLDA to EDTA is changed to 1:2.5.

[0156] Results: The heavy metal contents in the resin of the chromatographic column after cleaning in step 2 were as follows: lead: 20.12 μg / L; chromium: 45.86 μg / L; mercury: 25.71 μg / L; arsenic: 16.69 μg / L; cadmium: 23.20 μg / L; and the content of the target separation substance was 7.91%.

[0157] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 89.11%. The total adsorption rate of heavy metals was 86.03%.

[0158] Comparative Example 6

[0159] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total number of viable bacteria in the cleaning solution B remains unchanged, but only Leuconostoc citreum CGMCC 1.14, not included Pediococcus lolii CGMCC 1.528.

[0160] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 37.87μg / L; chromium: 74.57μg / L; mercury: 40.19μg / L; arsenic: 27.81μg / L; cadmium: 33.63μg / L; the content of the target separation substance was 12.34%.

[0161] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 84.07%. The total adsorption rate of heavy metals was 78.05%.

[0162] Comparative Example 7

[0163] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total number of viable bacteria in the cleaning solution B remains unchanged, but only Pediococcus lolii CGMCC 1.528, not included Leuconostoc citreum CGMCC 1.14.

[0164] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 35.66μg / L; chromium: 72.56μg / L; mercury: 38.87μg / L; arsenic: 27.29μg / L; cadmium: 35.76μg / L; the content of the target separation substance was 11.85%.

[0165] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 84.1%. The total adsorption rate of heavy metals was 79.72%.

[0166] Comparative Example 8

[0167] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total number of viable bacteria in the cleaning solution B remains unchanged, but the number of viable bacteria in the cleaning solution B is changed. Leuconostoc citreum CGMCC 1.14 and Pediococcus lolii The viable count ratio of CGMCC 1.528 is 1:4.

[0168] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 19.89μg / L; chromium: 47.79μg / L; mercury: 27.68μg / L; arsenic: 15.36μg / L; cadmium: 21.91μg / L; the content of the target separation substance was 8.01%.

[0169] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 88.96%. The total adsorption rate of heavy metals was 85.57%.

[0170] Comparative Example 9

[0171] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total number of viable bacteria in the cleaning solution B and the ratio of the two bacteria are not changed, and only the number of viable bacteria in the cleaning solution B is changed to Pediococcus lolii CGMCC 1.528 replaced by Weissella Weissella halotolerans CGMCC 1.2240.

[0172] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 32.75μg / L; chromium: 70.56μg / L; mercury: 37.18μg / L; arsenic: 24.35μg / L; cadmium: 33.14μg / L; the content of the target separation substance was 10.97%.

[0173] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 85.68%. The total adsorption rate of heavy metals was 81.78%.

[0174] Comparative Example 10

[0175] This comparative example provides a method for cleaning a resin filler. The cationic resin filler to be cleaned is the same as that in Example 2, and the cleaning method is basically the same as that in Example 2, except that the total number of viable bacteria in the cleaning solution B and the ratio of the two bacteria are not changed, and only the number of viable bacteria in the cleaning solution B is changed to Leuconostoc citreum CGMCC 1.14 replaced with Lactobacillus Lactobacillus fermentum CGMCC 1.15608.

[0176] Results: The heavy metal content of the resin in the chromatographic column after cleaning in step 2 was as follows: lead: 28.91μg / L; chromium: 66.75μg / L; mercury: 33.79μg / L; arsenic: 20.67μg / L; cadmium: 29.91μg / L; the content of the target separation substance was 10.39%.

[0177] The resin cleaned in step 2 was used as the filler of the chromatography column, and the same spiked skim milk was chromatographed according to the method in step 1. The adsorption rate of the cationic resin for the target separation substance after cleaning was 86.52%. The total adsorption rate of heavy metals was 83.13%.

[0178] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for cleaning a cationic resin, characterized in that: The cationic resin is firstly cleaned with cleaning solution A, and then with cleaning solution B; the cleaning solution A is an aqueous solution of a chelating agent; the chelating agent includes EDTA or its sodium salt and GLDA; the molar ratio of EDTA or its sodium salt to GLDA is (0.1-2):1; the pH of the cleaning solution A is 7.5-9; the cleaning solution B is a bacterial solution, the bacteria in the bacterial solution include Leuconostoc and Pediococcus; the ratio of the number of live bacteria of Leuconostoc to Pediococcus is 1:(0.4-3.6); the pH of the bacterial solution is 5-6.

5.

2. The method for cleaning cationic resin according to claim 1, characterized in that: The Leuconostoc is Leuconostoc citrinum or Leuconostoc mesenteroides; the Pediococcus is Pediococcus perenne.

3. The method for cleaning a cationic resin according to claim 1 or 2, characterized in that: The bacterial liquid is an aqueous solution of an organic acid or an organic acid salt of the bacteria; the organic acid is one or more of citric acid, lactic acid, malic acid, acetic acid, and tartaric acid; the organic acid salt is one or more of a sodium salt or a potassium salt of the organic acid.

4. The method for cleaning a cationic resin according to claim 1 or 2, characterized in that: In the cleaning solution A, the total concentration of the chelating agent is 0.008-0.29 mol / L; in the cleaning solution B, the total concentration of the bacteria is 5×10 7 -2×10 9 CFU / mL.

5. The method for cleaning cationic resin according to claim 1, characterized in that: The method of using cleaning solution A and cleaning solution B to clean the cationic resin is as follows: The cationic resin is mixed with cleaning solution A, and stirred for 1.5-3.5 hours for the first cleaning, and then the cationic resin that has been cleaned for the first time is mixed with cleaning solution B, and stirred for 30-60 minutes for the second cleaning; During the first cleaning, the volume of the cleaning solution A is 3-5 times the volume of the cationic resin; During the second cleaning, the volume of the cleaning solution B is 2-4 times the volume of the cationic resin that has been cleaned for the first time; The stirring speed during the first cleaning and the second cleaning is 180-300 rpm; The temperature of the cleaning solution A is 45-55°C; the temperature of the cleaning solution B is 25-35°C.

6. The method for cleaning cationic resin according to claim 1, characterized in that: When the cationic resin is loaded in a chromatography column, the cationic resin is cleaned by using cleaning solution A and cleaning solution B as follows: The cleaning solution A is injected into the chromatography column, and the volume of the cleaning solution A is 4-7 times the volume of the cationic resin; the total time for the cleaning solution A to flow through the cationic resin as a whole is 700-1100 seconds; then the cleaning solution B is injected into the chromatography column, and the volume of the cleaning solution B is 1.5-4 times the volume of the cationic resin; the total time for the cleaning solution B to flow through the cationic resin as a whole is 180-230 seconds; The temperature of the cleaning solution A is 45-55°C; the temperature of the cleaning solution B is 25-35°C.

7. The method for cleaning a cationic resin according to claim 5 or 6, characterized in that: After the cationic resin is cleaned by using cleaning solution A and cleaning solution B, the method further includes a step of washing the cationic resin with water.

8. A cationic resin cleaning solution, characterized in that: It comprises cleaning liquid A and cleaning liquid B; the cleaning liquid A and cleaning liquid B are as described in any one of claims 1-4.

9. Use of the method for cleaning a cationic resin according to any one of claims 1 to 7 in removing heavy metals from a cationic resin or in regenerating a chromatography column filled with a cationic resin.

10. A method for removing heavy metals from a product, characterized in that: include: After the heavy metals in the product are adsorbed by a chromatography column, the heavy metals in the filler of the chromatography column are removed by using the method for cleaning the cationic resin according to any one of claims 1 to 4 and 6 to 7; the filler is a cationic resin.