Method for recovering acid in chemical polishing liquid cleaning water by combining resin adsorption and diffusion dialysis

Abstract

The invention discloses a method for recovering acid in chemical polishing liquid cleaning water by combining resin adsorption and diffusion dialysis, belongs to the technical field of industrial waste liquid resourceful treatment, and aims to solve the technical problem that the purity and the concentration of purified acid recovered in the prior art need to be further improved. The method specifically comprises the following steps: introducing chemical polishing liquid cleaning water into an adsorption unit to obtain a dilute acid solution, introducing the dilute acid solution into a concentration unit for concentration to obtain recycled acid meeting the recycling standard of a chemical polishing tank, and after the adsorption unit achieves adsorption saturation, passing through a cleaning unit and then introducing into a desorption unit for desorption to obtain the recycled acid meeting the recycling standard of the chemical polishing tank. The adsorption liquid is introduced into a diffusion dialysis unit, purified acid and residual liquid are obtained, the finally obtained purified acid is circularly used for desorption treatment, and the residual liquid is directly discharged after being neutralized and filtered. The preparation of the cation adsorption resin is combined with the process flow, so that the purity and the concentration of the recovered acid are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial waste liquid resource treatment, in particular to a method for recovering acid in chemical polishing liquid cleaning water by resin adsorption-diffusion dialysis combination. BACKGROUND

[0002] In the field of aluminum anodic oxidation processing, the chemical polishing liquid cleaning water is a typical resource-pollutant dual system, which is rich in high-concentration acid resources and aluminum ions. If it is directly discharged, it will not only cause serious waste of valuable acid resources, but also greatly increase the difficulty and cost of subsequent sewage treatment, which does not meet the dual needs of resource recycling and environmental protection.

[0003] In order to realize the recycling of acid resources in chemical polishing liquid cleaning water, various related technologies have been developed in the industry, among which diffusion dialysis method, extraction method and traditional resin adsorption method are widely used. However, they all have significant technical defects. Diffusion dialysis method relies on membrane separation principle to separate acid and metal ions, but its recovery efficiency for specific acid is limited, and the subsequent disposal cost of residual liquid after treatment is high, which is difficult to achieve the balance between economy and environmental protection. Although the extraction method has the advantage of simple equipment structure, it has a large solvent loss during operation, which easily causes secondary pollution and limits its large-scale industrial application. Traditional resin adsorption method is one of the common technologies for acid recovery, but this method generally has acid retardation effect, and acid is prone to lag desorption in the resin, forming a long tail effect, which directly leads to low acid recovery efficiency. At the same time, a large amount of phosphorus residues will be accompanied in the desorption liquid, which brings many inconveniences to the subsequent treatment process, further affecting the stability and economy of the overall process.

[0004] In view of the technical defects in this regard, a solution is now proposed. SUMMARY

[0005] The purpose of the present application is to provide a method for recovering acid in chemical polishing liquid cleaning water by resin adsorption-diffusion dialysis combination, which solves the technical problem that the purity and concentration of the recovered purified acid need to be further improved in the prior art.

[0006] The purpose of the present application can be realized by the following technical solution: a method for recovering acid in chemical polishing liquid cleaning water by resin adsorption-diffusion dialysis combination, comprising the following steps:

[0007] S1, passing the chemical polishing liquid cleaning water into the adsorption unit, and obtaining a dilute acid solution from the adsorption unit after adsorption of the chemical polishing liquid cleaning water;

[0008] S2, passing the dilute acid solution into the concentration unit for concentration, and obtaining recovered acid meeting the chemical polishing tank recycling standard by concentrating to a specific gravity of 1.70;

[0009] S3, when the cation adsorption resin in S1 reaches adsorption saturation, the purified water is first used for intensive cleaning through the cleaning unit, then the desorption unit is connected, and the desorption is carried out by using sulfuric acid solution, the desorption liquid after intensive cleaning is connected to the diffusion dialysis unit, and the purified acid and the residual liquid are obtained;

[0010] S4, the purified acid is recycled for the desorption treatment in S3, and the residual liquid is directly discharged after being neutralized and filtered by the slaked lime.

[0011] Further, in step S1, the adsorption unit is filled with cation adsorption resin, and the adsorption unit is composed of 3-5 resin columns filled with cation adsorption resin in series; the specific gravity of the cleaning water is 1.05-1.20, and the flow rate of the purified water into the adsorption unit is 1.0-3.0 BV / h.

[0012] Further, in step S2, the concentration unit is connected to the outlet of the adsorption unit for concentrating the dilute acid liquid flowing out of the adsorption unit.

[0013] Further, in step S3, the desorption unit is connected to the adsorption unit, the flow rate of the purified water is 2 BV / h, the flow rate of the purified water into the desorption unit is 1.0-3.0 BV / h, the mass concentration of the sulfuric acid solution is 15-30%, the desorption amount is 0.8-1.5 BV; the diffusion dialysis unit is connected to the outlet of the desorption unit, the diffusion dialysis is composed of a tubular diffusion dialysis device, and the feed volume ratio of the desorption liquid to the purified water is 1:1.

[0014] Further, the cation adsorption resin is prepared by the following steps:

[0015] A1, chloromethylated polystyrene resin and ethylenediamine are added to a reaction kettle, refluxed at 80-90℃ for 6h, then post-treated to obtain aminated polystyrene resin;

[0016] A2, the aminated polystyrene resin is mixed with phosphorous acid, soaked for 20-30min, then heated to 100-110℃ for refluxing for 8-9h, cooled to 70℃, then maleic anhydride is added, and then heated to 90-100℃ for reaction for 4-5h, then post-treated to obtain the cation adsorption resin.

[0017] Reaction mechanism for preparing the cation adsorption resin:

[0018] The chloromethyl group of the chloromethylated polystyrene resin reacts with ethylenediamine to introduce amino groups, the pH is adjusted by concentrated hydrochloric acid to protonate the amino groups, finally, the amino groups of the aminated resin react with phosphorous acid to form amino phosphonic acid functional groups, then maleic anhydride is opened at high temperature to introduce carboxyl groups, and finally the cation adsorption resin with amino phosphonic acid and carboxyl dual functional sites is obtained through washing and drying.

[0019] Further, in step A1, the amount ratio of the chloromethylated polystyrene resin and ethylenediamine is 8g:9mL; in step A2, the amount ratio of the aminated polystyrene resin, phosphorous acid and maleic anhydride is 20g:30g:9-10g.

[0020] Further, in step A1, the chloromethylated polystyrene resin is prepared by the following steps:

[0021] B1, polyvinyl alcohol and hydroxypropyl methyl cellulose are added to a reaction kettle containing deionized water, stirred at 40-50℃ under nitrogen atmosphere for 20-30min, then an organic solution is added dropwise, after the dropwise addition is completed, first heated to 60-70℃ for 4-5h, then heated to 80-90℃ for 6-7h, post-treated to obtain a composite;

[0022] B2, the composite and chloromethyl ether are mixed, soaked for 30-40min, then cooled to 2-4℃, then anhydrous zinc chloride is added in three batches, each time stirring for 15-20min, after the addition is completed, heated to 30-40℃, continue to stir for 6-7h, post-treated to obtain the chloromethylated polystyrene resin.

[0023] Reaction mechanism for preparing the chloromethylated polystyrene resin:

[0024] Polyvinyl alcohol and hydroxypropyl methyl cellulose are dispersed in deionized water under nitrogen atmosphere to form a stable matrix, azobisisobutyronitrile in the organic solution is decomposed to generate free radicals by heating, which initiates the radical copolymerization and crosslinking of styrene and divinylbenzene, and then the matrix is compounded to form a network composite, then under the catalysis of anhydrous zinc chloride, the chloromethyl group of chloromethyl ether undergoes electrophilic substitution reaction with the benzene ring of the polystyrene segment in the composite to realize chloromethylation modification, and the chloromethylated polystyrene resin is obtained.

[0025] Further, in step B1, the organic solution is prepared by adding 65g of styrene, 22g of divinylbenzene and 1.2g of azobisisobutyronitrile into 150-160mL of anhydrous ethanol, and stirring at 20-30℃ until completely dissolved to obtain the organic solution; the amount ratio of polyvinyl alcohol, hydroxypropyl methyl cellulose, deionized water and organic solution is 0.5-0.6g:0.1g:120mL:50mL; in step B2, the amount ratio of the composite, chloromethyl ether and anhydrous zinc chloride is 10-11g:22mL:1.5g.

[0026] The present application has the following advantages:

[0027] 1. The cationic adsorption resin prepared by this invention has dual functional adsorption sites of aminophosphonic acid and carboxyl groups, which has a strong selective adsorption capacity for aluminum ions in the cleaning water of chemical polishing solution. It can efficiently capture aluminum ion impurities in the system and significantly reduce the residual amount of aluminum ions in the acid solution. The special structure of the resin makes its adsorption performance stable and highly targeted. It can accurately retain aluminum ions without affecting the existence form of acid, effectively avoiding the interference of aluminum ions on the purity of the recovered acid. Ultimately, it leads to a significant increase in the purity of the recovered acid and maintains the aluminum content at an extremely low level, which fully meets the core quality requirements for the reuse of chemical polishing tanks.

[0028] 2. The adsorption unit of this invention first achieves the initial separation of aluminum ions and acid. The concentration unit does not introduce additional impurities when increasing the acid concentration. The desorption unit reduces phosphorus residue through "pre-liquid merging" and "enhanced cleaning", which optimizes the resin regeneration effect and reduces the pressure of residual liquid treatment in subsequent diffusion dialysis. The diffusion dialysis unit further purifies the desorbed liquid to ensure high-purity acid recovery. The entire process adopts a closed-loop process of resin adsorption-concentration-desorption-diffusion dialysis, which is logically coherent and synergistically adapted. At the same time, the design of acid recycling and direct reuse of acid resources improves the acid recovery rate and reduces the total production cost. While continuously reducing aluminum ion residue, it achieves the dual benefits of steadily improving the purity of recovered acid and circular economy. Detailed Implementation

[0029] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] In this application, the polyvinyl alcohol is selected from Xiamen Minghuiyang Chemical Co., Ltd., CAS No. 9002-89-5, model No. 1788;

[0031] In this application, hydroxypropyl methylcellulose is selected from Henan Mingzhixin Chemical Products Co., Ltd., CAS No. 9004-65-3, with an active ingredient content of 99%.

[0032] Example 1

[0033] This embodiment provides a method for recovering acid from water by using a combination of resin adsorption-diffusion dialysis and chemical cleaning solution, including the following steps:

[0034] S1. Preparation of the complex

[0035] Weigh out 2.6 kg of styrene, 880 g of divinylbenzene and 48 g of azobisisobutyronitrile and add them to 6.0 L of anhydrous ethanol. Stir at 20 °C until completely dissolved to obtain an organic solution.

[0036] Weighing: 500g of polyvinyl alcohol and 100g of hydroxypropyl methyl cellulose are added to a reaction kettle containing 12L of deionized water, stirred at 40℃ under nitrogen atmosphere for 20min, then 5L of organic solution is added dropwise, after the dropwise addition is completed, first heated to 60℃ for 4h, then heated to 80℃ for 6h, after the reaction is completed, cooled to room temperature, filtered, washed with deionized water 3 times, then soaked in acetone for 2h, then transferred to a vacuum drying oven, dried at 60℃ for 12h, to obtain a composite;

[0037] S2, preparation of chloromethylated polystyrene resin

[0038] Weighing: 10kg of composite and 22L of chloromethyl ether are mixed, soaked for 30min, then cooled to 2℃, then 1.5kg of anhydrous zinc chloride is added in 3 batches, each time stirring for 15min, after the addition is completed, heated to 30℃, continue to stir for 6h, after the reaction is completed, washed with ice water and anhydrous ethanol 2 times respectively, then transferred to a vacuum drying oven, dried at 60℃ under vacuum for 10h, to obtain chloromethylated polystyrene resin;

[0039] S3, preparation of aminated polystyrene resin

[0040] Weighing: 8kg of chloromethylated polystyrene resin and 9L of ethylenediamine are added to a reaction kettle, refluxed at 80℃ for 6h, after the reaction is completed, add concentrated hydrochloric acid dropwise to adjust the pH to 3, stir for 20min, filter, washed with deionized water until neutral, then the product is transferred to a vacuum drying oven, dried at 60℃ for 8h, to obtain aminated polystyrene resin;

[0041] S4, preparation of cationic adsorption resin

[0042] Weighing: 20kg of aminated polystyrene resin and 30kg of phosphorous acid are mixed, soaked for 20min, then heated to 100℃ and refluxed for 8h, cooled to 70℃, then 9kg of maleic anhydride is added, then heated to 90℃ and reacted for 4h, after the reaction is completed, cooled to room temperature, washed with deionized water until neutral, then transferred to a vacuum drying oven, dried at 80℃ for 12h, passed through a 50 mesh sieve, then soaked in deionized water for 24h, filtered, to obtain cationic adsorption resin.

[0043] S5, adsorption treatment

[0044] The chemical polishing solution with a specific gravity of 1.05 is passed into a series adsorption unit composed of 3 resin columns filled with cationic adsorption resin at a flow rate of 1.0BV / h, and the chemical polishing solution after adsorption flows out of the adsorption unit to obtain a dilute acid solution.

[0045] S6, concentration treatment

[0046] The dilute acid solution is concentrated in the concentration unit connected to the outlet of the adsorption unit, and the concentration is 1.70, and the recovered acid meets the recycling standard of the chemical sludge.

[0047] S7, desorption treatment

[0048] When the cation exchange resin in S5 reaches adsorption saturation, the desorption unit connected to the outlet of the adsorption unit is used to desorb the desorption liquid after the enhanced washing with pure water at a flow rate of 2BV / h, and then 15wt% sulfuric acid solution is used to desorb at a flow rate of 1.0BV / h. When the desorption amount reaches 0.8BV, the desorption liquid after the enhanced washing is mixed with pure water at a volume ratio of 1:1 and introduced into the diffusion dialysis unit composed of a tubular diffusion dialysis device connected to the outlet of the desorption unit, to obtain purified acid and residual liquid.

[0049] S8, recovery liquid treatment

[0050] The purified acid is recycled for desorption treatment in S7, and the residual liquid is neutralized with lime and filtered before being discharged directly.

[0051] Example 2

[0052] The method provided in this embodiment for recovering acid in the cleaning water of chemical sludge by resin adsorption-diffusion dialysis combination comprises the following steps:

[0053] S1, preparation of composite

[0054] Weigh 2.6kg of styrene, 880g of divinylbenzene and 48g of azobisisobutyronitrile into 6.2L of anhydrous ethanol, stir at 25℃ until completely dissolved, and obtain an organic solution;

[0055] Weigh 550g of polyvinyl alcohol and 100g of hydroxypropyl methyl cellulose into a reaction kettle containing 12L of deionized water, stir at 45℃ under nitrogen atmosphere for 25min, then add 5L of the organic solution dropwise, first heat to 65℃ and react for 4.5h, then heat to 85℃ and react for 6.5h, cool to room temperature after reaction, filter, wash the product with deionized water 4 times, then soak in acetone for 2h, then transfer to a vacuum drying oven and dry at 65℃ for 13h, to obtain the composite;

[0056] S2, preparation of chloromethylated polystyrene resin

[0057] Take: 10 kg of the composite and 22 L of chloromethyl ether mixed, soaked for 35 min, cooled to 3℃, then 1.5 kg of anhydrous zinc chloride was added in 3 batches, each time stirring for 15 min, after the addition was completed, the temperature was raised to 35℃, and the stirring was continued for 6.5 h, after the reaction was completed, washed with ice water and anhydrous ethanol 2 times respectively, then transferred to a vacuum drying oven, dried at 60℃ for 10 h, to obtain chloromethylated polystyrene resin;

[0058] S3, preparation of aminated polystyrene resin

[0059] Take: 8 kg of chloromethylated polystyrene resin and 9 L of ethylenediamine were added to the reaction kettle, refluxed at 85℃ for 6 h, after the reaction was completed, the pH was adjusted to 3.5 by adding concentrated hydrochloric acid dropwise, stirred for 25 min, filtered, washed with deionized water until neutral, and then transferred to a vacuum drying oven, dried at 60℃ for 8 h, to obtain aminated polystyrene resin;

[0060] S4, preparation of cationic adsorption resin

[0061] Take: 20 kg of aminated polystyrene resin and 30 kg of phosphorous acid were mixed, soaked for 25 min, then the temperature was raised to 100℃ and refluxed for 8.5 h, cooled to 70℃, then 9.5 kg of maleic anhydride was added, and the temperature was raised to 95℃ and reacted for 4.5 h, after the reaction was completed, cooled to room temperature, washed with deionized water until neutral, then transferred to a vacuum drying oven, dried at 80℃ for 12 h, sieved through a 50 mesh sieve, then soaked in deionized water for 24 h, filtered, to obtain cationic adsorption resin.

[0062] S5, adsorption treatment

[0063] The chemical polishing liquid with a specific gravity of 1.1 was passed into the adsorption unit connected in series by 4 resin columns filled with cationic adsorption resin at a flow rate of 2.0 BV / h, and the chemical polishing liquid after adsorption flowed out of the adsorption unit to obtain a dilute acid solution.

[0064] S6, concentration treatment

[0065] The dilute acid solution was passed into the concentration unit connected to the outlet of the adsorption unit for concentration, and concentrated to a specific gravity of 1.70 to obtain recovered acid meeting the recycling standard of the chemical polishing tank.

[0066] S7, desorption treatment

[0067] When the cation adsorption resin in S5 reaches adsorption saturation, the adsorption unit is connected to a washing unit, and first, pure water is used to perform intensive washing at a flow rate of 2 BV / h, and then 20wt% sulfuric acid solution is used to perform desorption in a desorption unit connected to the adsorption unit at a flow rate of 2.0 BV / h. When the desorption amount reaches 1.2 BV, the desorption liquid after intensive washing and pure water are mixed at a volume ratio of 1:1 and are introduced into a diffusion dialysis unit composed of a tubular diffusion dialysis device connected to the outlet of the desorption unit, to obtain purified acid and residual liquid.

[0068] S8, recovery liquid treatment

[0069] The purified acid is recycled for desorption treatment in S7, and the residual liquid is directly discharged after being neutralized by slaked lime and filtered.

[0070] Example 3

[0071] The present embodiment provides a method for recovering acid in waste liquid cleaning water by using resin adsorption-diffusion dialysis, comprising the following steps:

[0072] S1, preparation of composite: 2.6 kg of styrene, 880 g of divinylbenzene and 48 g of azobisisobutyronitrile are added to 6.4 L of anhydrous ethanol, and stirred at 30°C until completely dissolved to obtain an organic solution;

[0073] Weigh 600 g of polyvinyl alcohol and 100 g of hydroxypropyl methyl cellulose into a reaction kettle containing 12 L of deionized water, stir under nitrogen atmosphere at 50°C for 30 min, then add 5 L of organic solution dropwise, first heat to 70°C for 5 h, then heat to 90°C for 7 h, after the reaction is completed, cool to room temperature, filter, wash the product with deionized water 5 times, then soak in acetone for 2 h, then transfer to a vacuum drying oven and dry at 70°C for 14 h to obtain the composite;

[0074] S2, preparation of chloromethylated polystyrene resin

[0075] Weigh 11 kg of composite and 22 L of chloromethyl ether, soak for 40 min, then cool to 4°C, add 1.5 kg of anhydrous zinc chloride in 3 batches, stir for 20 min each time, after adding, heat to 40°C and continue to stir for 7 h, after the reaction is completed, wash with ice water and anhydrous ethanol 3 times respectively, then transfer to a vacuum drying oven and dry at 60°C for 10 h to obtain chloromethylated polystyrene resin;

[0076] S3, preparation of aminated polystyrene resin

[0077] Weighing: 8 kg of chloromethylated polystyrene resin and 9 L of ethylenediamine are added to the reaction kettle, and after refluxing at 90°C for 6 h, the reaction is completed. After adjusting the pH to 4 by adding concentrated hydrochloric acid dropwise, stirring for 30 min, and filtering, the product is washed with deionized water until it is neutral. The product is then transferred to a vacuum drying oven and dried at 60°C for 8 h to obtain the aminated polystyrene resin.

[0078] S4, Preparation of a cation adsorption resin

[0079] Weighing: 20 kg of aminated polystyrene resin and 30 kg of phosphorous acid are mixed and soaked for 30 min. The temperature is then raised to 110°C and refluxed for 9 h. After cooling to 70°C, 10 kg of maleic anhydride is added, and the temperature is raised to 100°C and reacted for 5 h. After the reaction is completed, the temperature is cooled to room temperature, and the product is washed with deionized water until it is neutral. Finally, it is transferred to a vacuum drying oven and dried at 80°C for 12 h. The product is then sieved through a 50-mesh sieve and soaked in deionized water for 24 h. After filtering, the cation adsorption resin is obtained.

[0080] S5, Adsorption treatment

[0081] The pickling solution with a specific gravity of 1.20 is passed into the adsorption unit at a flow rate of 3.0 BV / h, and the pickling solution after adsorption is discharged from the adsorption unit to obtain a dilute acid solution.

[0082] S6, Concentration treatment

[0083] The dilute acid solution is passed into the concentration unit connected to the outlet of the adsorption unit for concentration. The concentration is carried out until the specific gravity reaches 1.70, and the recovered acid that meets the recycling standard of the pickling tank is obtained.

[0084] S7, Desorption treatment

[0085] When the cation adsorption resin in S5 reaches adsorption saturation, it is first subjected to intensive washing with pure water at a flow rate of 2 BV / h, and then passed into the desorption unit connected to the adsorption unit at a flow rate of 3.0 BV / h. A 30 wt% sulfuric acid solution is used for desorption. When the desorption amount reaches 1.5 BV, the desorption solution after intensive washing is mixed with pure water at a volume ratio of 1:1 and passed into the diffusion dialysis unit composed of a tubular diffusion dialysis device connected to the outlet of the desorption unit. Purified acid and residual liquid are obtained.

[0086] S8, Treatment of recovered liquid

[0087] The purified acid is recycled for desorption treatment in step S7, and the residual liquid is neutralized with lime and filtered before being directly discharged.

[0088] Comparative Example 1

[0089] The difference between the present comparative example and Example 3 is that the preparation of the cation adsorption resin is cancelled, and a commercially available cation adsorption resin is used to replace the cation adsorption resin in step S5.

[0090] Performance test:

[0091] The mass concentration of aluminum ions contained in the purified acid recovered from Examples 1-3 and Comparative Example 1 is determined according to the standard GB / T 23837-2009 "Determination of Aluminum Ions in Industrial Circulating Cooling Water-Atomic Absorption Spectrometry".

[0092] The mass molar concentration of the purified acid recovered from Examples 1-3 and Comparative Example 1 is determined according to the standard GB / T 9736-2008 "Chemical Reagents-General Method for Determination of Acidity and Alkalinity", and the specific test results are shown in Table 1 below:

[0093] Table 1-Performance test data table of the sample

[0094]

[0095] Data analysis:

[0096] Comparative analysis of the data in Table 1 above, the mass molar concentration of the purified acid recovered by the present application is 414 mmol / g, and the aluminum ion content in the recovered purified acid is 4836 mg / L;

[0097] Comparative Example 1 uses a commercially available cation adsorption resin, which lacks the amino phosphonic acid and carboxyl bifunctional adsorption sites possessed by the self-made resin of the present application, resulting in insufficient selective adsorption of aluminum ions in the cleaning water of the polishing solution, and unable to efficiently capture aluminum ion impurities, thereby increasing the aluminum ion content in the recovered purified acid to 6425 mg / L. At the same time, the commercially available resin is difficult to alleviate the acid retardation effect of the traditional resin adsorption method, and the acid is prone to lag desorption in the resin, and cannot form close cooperation with the subsequent concentration, desorption, and diffusion dialysis unit, resulting in reduced acid recovery efficiency, and further reducing the mass molar concentration of the purified acid. In addition, the adsorption and desorption performance stability of the commercially available resin is insufficient, and it is difficult to effectively reduce the impurity residues in the desorption liquid through intensified cleaning, further affecting the purification effect of the diffusion dialysis unit, ultimately resulting in higher aluminum ion residues and lower acid concentration, and the comprehensive recovery performance is inferior to that of the present application.

[0098] The preferred embodiments of the application disclosed above are only to facilitate the elucidation of the application. The preferred embodiments do not describe all the details of the application and limit the application to the specific embodiments. Obviously, many modifications and variations can be made in light of the teachings above. The description is chosen and described in order to provide the best illustration of the application and its practical application to those skilled in the art and to enable those skilled in the art to best utilize the application. The application is limited only by the claims and their full scope and equivalents.

Claims

1. A method for recovering acid from rinse water in a resin adsorption-diffusion dialysis combination process, characterized by, The method comprises the following steps: S1, the pickling liquid cleaning water is introduced into the adsorption unit, and the pickling liquid cleaning water after adsorption flows out of the adsorption unit to obtain a dilute acid solution; S2, the dilute acid solution is introduced into the concentration unit for concentration, and the concentration is performed to a specific gravity of 1.70 to obtain recovered acid meeting the recycling standard of the pickling groove; S3, when the cation adsorption resin in S1 reaches adsorption saturation, the cation adsorption resin is subjected to intensive cleaning by using pure water through the cleaning unit, and then is introduced into the desorption unit to be desorbed by using a sulfuric acid solution, the desorbed liquid after the intensive cleaning is introduced into the diffusion dialysis unit to obtain purified acid and residual liquid; S4, the purified acid is recycled for the desorption treatment in S3, and the residual liquid is directly discharged after being neutralized by lime and filtered.

2. The method for recovering acid from the rinse water of the chemical polishing solution according to claim 1, wherein In S1, the adsorption unit is internally filled with cation adsorption resin, and the adsorption unit is composed of 3-5 resin columns filled with cation adsorption resin and connected in series; the pickling liquid cleaning water has a specific gravity of 1.05-1.20, and the flow rate introduced into the adsorption unit is 1.0-3.0 BV / h.

3. The method for recovering acid from the rinse water of the chemical polishing solution by the resin adsorption-diffusion dialysis combination according to claim 2, characterized in that, In S2, the concentration unit is connected with the liquid outlet of the adsorption unit, and is used for concentrating the dilute acid solution flowing out of the adsorption unit.

4. The method for recovering acid from the rinse water of the chemical polishing solution according to claim 2, wherein In S3, the desorption unit is connected with the adsorption unit, the flow rate of the pure water is 2 BV / h, the flow rate introduced into the desorption unit is 1.0-3.0 BV / h, the mass concentration of the sulfuric acid solution is 15-30%, and the desorption amount is 0.8-1.5 BV; the diffusion dialysis unit is connected with the liquid outlet of the desorption unit, the diffusion dialysis is composed of a tubular diffusion dialysis device, and the feed volume ratio of the desorbed liquid to pure water is 1:

1.

5. The method for recovering acid from the rinse water of the chemical polishing solution according to claim 2, wherein The cation adsorption resin is prepared by the following steps: A1, chloromethylated polystyrene resin and ethylenediamine are added to a reaction kettle, refluxed at 80-90 DEG C for 6h, and then post-treated to obtain aminated polystyrene resin; A2, the aminated polystyrene resin is mixed with phosphorous acid, soaked for 20-30 min, heated to 100-110 DEG C and refluxed for 8-9h, cooled to 70 DEG C, added with maleic anhydride, heated to 90-100 DEG C and reacted for 4-5h, and then post-treated to obtain the cation adsorption resin.

6. The method for recovering acid from the rinse water of the chemical polishing solution according to claim 5, wherein In A1, the amount ratio of the chloromethylated polystyrene resin to ethylenediamine is 8g:9mL; in A2, the amount ratio of the aminated polystyrene resin, phosphorous acid and maleic anhydride is 20g:30g:9-10g.

7. The method for recovering acid from the rinse water of the chemical mechanical polishing according to claim 5, wherein the acid is recovered from the rinse water of the chemical mechanical polishing by the resin adsorption-diffusion dialysis combination method. In A1, the chloromethylated polystyrene resin is prepared by the following steps: B1, polyvinyl alcohol and hydroxypropyl methyl cellulose are added to a reaction kettle containing deionized water, stirred at 40-50 DEG C under a nitrogen atmosphere for 20-30 min, then an organic solution is added dropwise, heated to 60-70 DEG C and reacted for 4-5h, then heated to 80-90 DEG C and reacted for 6-7h, and then post-treated to obtain a composite; B2, the compound and chloromethyl ether are mixed, soaked for 30-40 min, then cooled to 2-4℃, then anhydrous zinc chloride is added in three batches, each time stirring for 15-20 min, after the addition is completed, the temperature is raised to 30-40℃, and stirring is continued for 6-7 h, then post-treated to obtain chloromethylated polystyrene resin.

8. The method for recovering acid from the rinse water of the chemical mechanical polishing according to claim 7, wherein the acid is recovered from the rinse water of the chemical mechanical polishing by the resin adsorption-diffusion dialysis combination method. In step B1, the organic solution is obtained by adding 65 g of styrene, 22 g of divinylbenzene and 1.2 g of azobisisobutyronitrile to 150-160 mL of anhydrous ethanol, and stirring at 20-30℃ until completely dissolved; the use amount ratio of polyvinyl alcohol, hydroxypropyl methyl cellulose, deionized water and organic solution is 0.5-0.6 g: 0.1 g: 120 mL: 50 mL; in step B2, the use amount ratio of the compound, chloromethyl ether and anhydrous zinc chloride is 10-11 g: 22 mL: 1.5 g.

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