Vein industry resin waste solvent recycling method

Abstract

The invention belongs to the technical field of waste treatment and cyclic utilization, and particularly relates to a vein industry resin waste solvent cyclic utilization method. The method comprises the following steps: S1, adding a modified flocculant into a vinyl ester resin-containing resin waste solvent generated in vein industry, and separating by an extraction method to obtain a vinyl ester resin-containing mixed solution; s2, filtering the mixed solution containing the vinyl ester resin by using an ultrafiltration membrane separation technology to obtain a vinyl ester resin mixed solution; s3, adding acetic acid into the vinyl ester resin mixed solution to adjust the pH value, adding a modified separating agent, and extracting again to obtain a crude vinyl ester resin solution; and S4, heating and distilling the crude vinyl ester resin, and further purifying to obtain a vinyl ester resin solution. The recycling method provided by the invention not only reduces the emission of the waste solvent, but also reduces the treatment cost and improves the economic benefits of enterprises.

Description

Technical Field

[0001] The invention belongs to the technical field of waste treatment and recycling, and specifically relates to a method for recycling waste solvent of venous chemical industry resin. Background Art

[0002] With the acceleration of industrialization, the venous industry (i.e., resource recycling and environmental protection industry) has become an important force in promoting sustainable development and has received increasing attention from all walks of life. In the venous industry, resin materials are widely used, including but not limited to water treatment, ion exchange, catalyst carriers and other fields. However, resin materials will produce a large amount of waste solvents during long-term use and regeneration. These solvents often contain a variety of harmful substances, such as heavy metal ions, organic pollutants, etc. If they are directly discharged into the environment, they will cause serious pollution and damage to the soil, water sources and ecosystems.

[0003] Vinyl ester resin is widely used in various fields due to its unique properties. In terms of anti-corrosion materials, it is used to make anti-corrosion coatings, linings and structural materials, especially in the chemical, petroleum, and power industries. At the same time, vinyl ester resin is also used to produce high-quality FRP (fiber reinforced plastic) products, such as electrical insulation components, industrial pumps and valves, sports equipment (such as golf club heads), etc. It can also be used to make corrosion-resistant storage tanks, pipelines, floor coatings, etc. By recycling vinyl ester resin, companies can reduce the demand for new raw materials and thus reduce production costs. Recycling vinyl ester resin in resin waste solution is of great significance, which not only contributes to environmental protection and sustainable development, but also brings economic benefits and resource conservation. At the same time, it is also an important way to promote technological innovation and industrial upgrading. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method for recycling waste solvents of venous chemical industry resins.

[0005] To achieve the above object, the present invention provides the following technical solutions: A method for recycling waste solvents from venous industrial resins comprises the following steps: S1. Add 15-20 parts of a modified flocculant to 50-80 parts of a resin waste solvent containing a vinyl ester resin produced in the venous industry, and separate the mixture containing the vinyl ester resin by extraction; S2. The mixed solution containing the vinyl ester resin is filtered using an ultrafiltration membrane separation technique to obtain a vinyl ester resin mixed solution; S3. Add 1-3 parts of acetic acid to the vinyl ester resin mixture to adjust the pH and add 2-5 parts of a modified separating agent, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is heated and distilled to further purify it to obtain a vinyl ester resin solution.

[0006] The modified flocculant is prepared by the following steps: S101. Place 10-15 parts of polyoxypropyl glyceryl ether and 8-12 parts of xylene solution into a reaction vessel, mechanically stir for 3-5 minutes at a temperature of 90-150° C. to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 2-5 min, 5-10 parts of activated carbon and 20-25 parts of deionized water were mixed with the preliminary mixture and mechanically stirred to obtain a secondary mixture; S103. Add 3-6 parts of the modified liquid to the mixture of the second step, stir at 40-50° C. until a stable emulsion is formed to obtain a modified flocculant.

[0007] Preferably, in step S2, the operating pressure of the ultrafiltration membrane separation technology is 0.2-0.4 MPa, and the molecular weight cutoff of the ultrafiltration membrane is 8000-12000 Daltons.

[0008] Preferably, in step S2, acetic acid is used to adjust the pH to a range of 6.4-6.8.

[0009] Preferably, in step S103, the modified liquid is a mixture of diammonium phosphate and polyferric phosphorus chloride in a mass ratio of 1-3:1.5-2.

[0010] Preferably, in step S3, the preparation of the modified separating agent comprises the following steps: S201. Add 2-5 parts of sodium sulfide solution and 1-3 parts of xylene solution into a beaker and stir at a stirring speed of 300-500 r / min, a temperature of 30-40 ° C, and a reaction time of 5-10 min to obtain a preliminary mixed solution; S202. Add 0.5-2 parts of tetrahydrofuran solution and 10-15 parts of deionized water to the preliminary mixed solution and stir to obtain a modified separating agent.

[0011] Preferably, in step S202, the stirring speed is 400-600 r / min, the temperature is 60-70° C., and the reaction time is 10-15 min.

[0012] Preferably, the modified separation agent in step S3 also reacts with the excess modified flocculant in step S1.

[0013] Preferably, the temperature of the heating distillation in step S4 is 90-100°C.

[0014] Preferably, in step S102, the stirring speed is 400-500 r / min, and the reaction time is 5-8 min.

[0015] Preferably, in step S103, the stirring speed is 450-550 r / min, and the reaction time is 15-20 min.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention recycles the vinyl ester resin in the resin waste solution, which is environmentally friendly and not only contributes to environmental protection and sustainable development, but also brings economic benefits and saves resources.

[0017] 2. The flocculant can be modified to effectively avoid the vinyl ester resin in the resin waste solution, and at the same time, it is combined with the modified liquid to separate the impurities, heavy metal elements, phosphorus, etc. in the waste solution from the vinyl ester resin, and the excess modified flocculant is mixed with the modified separation agent, so that the present invention achieves the best separation effect.

[0018] 3. The recycling method provided by the present invention not only reduces the emission of waste solvents, but also reduces the processing costs and improves the economic benefits of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a flow chart of the method for recycling waste solvent of resin in the venous chemical industry. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] See also Figure 1 , the present invention provides a technical solution: Example 1 A method for recycling waste solvents from venous industrial resins: S1. 15 parts of a modified flocculant were added to 50 parts of a resin waste solvent containing a vinyl ester resin produced in the intravenous industry, and a mixed solution containing a vinyl ester resin was separated by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.2MPa, and the molecular weight cutoff of the ultrafiltration membrane was 8000 Daltons to obtain a vinyl ester resin mixture; S3. Add 1 part of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.4 and add 2 parts of a modified separation agent, react with an excess of the modified flocculant in the vinyl ester resin mixture, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is further purified by heating and distillation at a temperature of 90° C. to finally obtain a vinyl ester resin solution.

[0022] The modified flocculant is prepared by the following steps: S101. 10 parts of polyoxypropyl glyceryl ether and 8 parts of xylene solution were placed in a reaction vessel and mechanically stirred for 3 minutes at a temperature of 90°C to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 2 min, 5 parts of activated carbon and 20 parts of deionized water were mixed with the preliminary mixture and mechanically stirred at a stirring speed of 400 r / min and a reaction time of 5 min to obtain a secondary mixture; S103. Add 3 parts of a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride into the mixture of the second step, stir at 40°C, with a stirring speed of 450 r / min and a reaction time of 15 min until a stable emulsion is formed to obtain a modified flocculant.

[0023] The preparation of the modified separating agent comprises the following steps: S201. Add 2 parts of sodium sulfide solution and 1 part of xylene solution into a beaker and stir at a stirring speed of 300 r / min, a temperature of 30° C., and a reaction time of 5 min to obtain a preliminary mixed solution; S202. Add 0.5 parts of tetrahydrofuran solution and 10 parts of deionized water to the preliminary mixed liquid and stir at a stirring speed of 400 r / min, a temperature of 60° C., and a reaction time of 10 min to finally obtain a modified separating agent.

[0024] Example 2 A method for recycling waste solvents from venous industrial resins: S1. 20 parts of a modified flocculant were added to 80 parts of a resin waste solvent containing a vinyl ester resin produced in the venous industry, and a mixed solution containing a vinyl ester resin was separated by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.4MPa, and the molecular weight cutoff of the ultrafiltration membrane was 12000 Daltons to obtain a vinyl ester resin mixture; S3. Add 3 parts of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.8 and add 5 parts of a modified separation agent, react with an excess of the modified flocculant in the vinyl ester resin mixture, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is further purified by heating and distillation at a temperature of 100° C. to finally obtain a vinyl ester resin solution.

[0025] The modified flocculant is prepared by the following steps: S101. 15 parts of polyoxypropyl glyceryl ether and 12 parts of xylene solution were placed in a reaction vessel and mechanically stirred for 5 min at a temperature of 150 ° C to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 5 min, 10 parts of activated carbon and 25 parts of deionized water were mixed with the preliminary mixture and mechanically stirred at a stirring speed of 500 r / min and a reaction time of 8 min to obtain a secondary mixture; S103. Add 6 parts of a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride into the mixture of the second step, stir at 50°C, with a stirring speed of 550 r / min and a reaction time of 20 min until a stable emulsion is formed to obtain a modified flocculant.

[0026] The preparation of the modified separating agent comprises the following steps: S201. Add 5 parts of sodium sulfide solution and 3 parts of xylene solution into a beaker and stir at a stirring speed of 500 r / min, a temperature of 40° C., and a reaction time of 10 min to obtain a preliminary mixed solution; S202. Add 2 parts of tetrahydrofuran solution and 15 parts of deionized water to the preliminary mixed solution and stir at a stirring speed of 600 r / min, a temperature of 70° C., and a reaction time of 15 min to finally obtain a modified separating agent.

[0027] Example 3 A method for recycling waste solvents from venous industrial resins: S1. 16 parts of a modified flocculant were added to 60 parts of a resin waste solvent containing a vinyl ester resin produced in the venous industry, and a mixed solution containing a vinyl ester resin was separated by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.3MPa, and the molecular weight cutoff of the ultrafiltration membrane was 9000 Daltons to obtain a vinyl ester resin mixture; S3. Add 2 parts of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.5 and add 3 parts of a modified separation agent, react with an excess of the modified flocculant in the vinyl ester resin mixture, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is further purified by heating and distillation at a temperature of 92° C. to finally obtain a vinyl ester resin solution.

[0028] The modified flocculant is prepared by the following steps: S101. 11 parts of polyoxypropyl glyceryl ether and 9 parts of xylene solution were placed in a reaction vessel and mechanically stirred for 4 minutes at a temperature of 100° C. to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 3 min, 6 parts of activated carbon and 21 parts of deionized water were mixed with the preliminary mixture and mechanically stirred at a stirring speed of 450 r / min and a reaction time of 6 min to obtain a secondary mixture; S103. Add 4 parts of a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride into the mixture of the second step, stir at 42°C, with a stirring speed of 500 r / min and a reaction time of 16 min until a stable emulsion is formed to obtain a modified flocculant.

[0029] The preparation of the modified separating agent comprises the following steps: S201. Add 3 parts of sodium sulfide solution and 2 parts of xylene solution into a beaker and stir at a stirring speed of 350 r / min, a temperature of 32° C., and a reaction time of 6 min to obtain a preliminary mixed solution; S202. Add 1 part of tetrahydrofuran solution and 11 parts of deionized water to the preliminary mixed solution and stir at a stirring speed of 500 r / min, a temperature of 62° C., and a reaction time of 11 min to finally obtain a modified separating agent.

[0030] Example 4 A method for recycling waste solvents from venous industrial resins: S1. 19 parts of a modified flocculant were added to 70 parts of a resin waste solvent containing a vinyl ester resin produced in the venous industry, and a mixed solution containing a vinyl ester resin was separated by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.3MPa, and the molecular weight cutoff of the ultrafiltration membrane was 11000 Daltons to obtain a vinyl ester resin mixture; S3. Add 2 parts of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.7 and add 4 parts of a modified separation agent, react with an excess of the modified flocculant in the vinyl ester resin mixture, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is further purified by heating and distillation at a temperature of 98° C. to finally obtain a vinyl ester resin solution.

[0031] The modified flocculant is prepared by the following steps: S101. 14 parts of polyoxypropyl glyceryl ether and 11 parts of xylene solution were placed in a reaction vessel and mechanically stirred for 4 minutes at a temperature of 140°C to obtain a preliminary mixture; S102. The activated carbon was physically crushed by a hammer mill for 4 min, 9 parts of activated carbon and 24 parts of deionized water were mixed with the preliminary mixture and mechanically stirred at a stirring speed of 450 r / min and a reaction time of 7 min to obtain a secondary mixture; S103. Add 5 parts of a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride into the mixture of the second step, stir at 58°C, with a stirring speed of 500 r / min and a reaction time of 19 min until a stable emulsion is formed to obtain a modified flocculant.

[0032] The preparation of the modified separating agent comprises the following steps: S201. Add 4 parts of sodium sulfide solution and 2 parts of xylene solution into a beaker and stir at a stirring speed of 450 r / min, a temperature of 38° C., and a reaction time of 9 min to obtain a preliminary mixed solution; S202. Add 1.5 parts of tetrahydrofuran solution and 14 parts of deionized water to the preliminary mixed liquid and stir at a stirring speed of 550 r / min, a temperature of 68° C., and a reaction time of 14 min to finally obtain a modified separating agent.

[0033] Comparative Example 1 A method for recycling waste solvents from venous industrial resins: S1. 15 parts of polyacrylamide were added to 50 parts of the waste solvent containing vinyl ester resin produced in the intravenous industry, and the mixture containing vinyl ester resin was separated by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.2MPa, and the molecular weight cutoff of the ultrafiltration membrane was 8000 Daltons to obtain a vinyl ester resin mixture; S3. Add 1 part of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.4 and add 2 parts of a modified separating agent, react with excess polyacrylamide in the vinyl ester resin mixture, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is heated and distilled to further purify the resin. The temperature of the heating and distillation is 90°C. The preparation of the modified separating agent comprises the following steps: S201. Add 2 parts of sodium sulfide solution and 1 part of xylene solution into a beaker and stir at a stirring speed of 300 r / min, a temperature of 30° C., and a reaction time of 5 min to obtain a preliminary mixed solution; S202. Add 0.5 parts of tetrahydrofuran solution and 10 parts of deionized water to the preliminary mixed liquid and stir at a stirring speed of 400 r / min, a temperature of 60° C., and a reaction time of 10 min to finally obtain a modified separating agent.

[0034] Comparative Example 2 A method for recycling waste solvents from venous industrial resins: S1. 15 parts of a modified flocculant were added to 50 parts of a resin waste solvent containing a vinyl ester resin produced in the intravenous industry, and a mixed solution containing a vinyl ester resin was separated by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.2MPa, and the molecular weight cutoff of the ultrafiltration membrane was 8000 Daltons to obtain a vinyl ester resin mixture; S3. Add 1 part of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.4 and add 2 parts of sodium sulfide to react with the excess modified flocculant in the vinyl ester resin mixture, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is further purified by heating and distillation at a temperature of 90° C. to finally obtain a vinyl ester resin solution.

[0035] The modified flocculant is prepared by the following steps: S101. 10 parts of polyoxypropyl glyceryl ether and 8 parts of xylene solution were placed in a reaction vessel and mechanically stirred for 3 minutes at a temperature of 90°C to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 2 min, 5 parts of activated carbon and 20 parts of deionized water were mixed with the preliminary mixture and mechanically stirred at a stirring speed of 400 r / min and a reaction time of 5 min to obtain a secondary mixture; S103. Add 3 parts of a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride into the mixture of the second step, stir at 40°C, with a stirring speed of 450 r / min and a reaction time of 15 min until a stable emulsion is formed to obtain a modified flocculant.

[0036] Comparative Example 3 A method for recycling waste solvents from venous industrial resins: S1. Add 5 parts of a modified flocculant to 50 parts of a resin waste solvent containing a vinyl ester resin produced in the intravenous industry, and all react with the solution without residue, and separate the mixture containing the vinyl ester resin by extraction; S2. The mixed solution containing the vinyl ester resin was filtered using an ultrafiltration membrane separation technique, the operating pressure of the ultrafiltration membrane separation technique was 0.2MPa, and the molecular weight cutoff of the ultrafiltration membrane was 8000 Daltons to obtain a vinyl ester resin mixture; S3. Add 1 part of acetic acid to the vinyl ester resin mixture to adjust the pH to 6.4 and add 2 parts of a modified separating agent, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is further purified by heating and distillation at a temperature of 90° C. to finally obtain a vinyl ester resin solution.

[0037] The modified flocculant is prepared by the following steps: S101. 10 parts of polyoxypropyl glyceryl ether and 8 parts of xylene solution were placed in a reaction vessel and mechanically stirred for 3 minutes at a temperature of 90°C to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 2 min, 5 parts of activated carbon and 20 parts of deionized water were mixed with the preliminary mixture and mechanically stirred at a stirring speed of 400 r / min and a reaction time of 5 min to obtain a secondary mixture; S103. Add 3 parts of a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride into the mixture of the second step, stir at 40°C, with a stirring speed of 450 r / min and a reaction time of 15 min until a stable emulsion is formed to obtain a modified flocculant.

[0038] The preparation of the modified separating agent comprises the following steps: S201. Add 2 parts of sodium sulfide solution and 1 part of xylene solution into a beaker and stir at a stirring speed of 300 r / min, a temperature of 30° C., and a reaction time of 5 min to obtain a preliminary mixed solution; S202. Add 0.5 parts of tetrahydrofuran solution and 10 parts of deionized water to the preliminary mixed liquid and stir at a stirring speed of 400 r / min, a temperature of 60° C., and a reaction time of 10 min to finally obtain a modified separating agent.

[0039] Performance Testing: The vinyl ester resin solutions obtained in Examples 1-4 and Comparative Examples 1-3 were tested for performance respectively. The mass fraction of the vinyl ester resin was detected by titration with potassium hydroxide solution; the suspended solids (SS) were detected by weight method; the color was detected by dilution multiple method; the turbidity was detected by scattered light method; the ammonia nitrogen (NH3-N) was detected by Nessler's reagent spectrophotometry; and the total phosphorus (TP) was detected by ammonium molybdate spectrophotometry. The test results are shown in Table 1 below: Table 1 In the process of setting up the experiment, Comparative Example 1 lacks the modified defoaming agent compared to Example 1, and a conventional flocculant is used to treat the waste resin solvent containing vinyl ester resin. Comparative Example 2 lacks the use of a modified separating agent compared to Example 1, and a conventional separating agent is used to treat the vinyl ester resin mixed solution. The modified flocculant added in Comparative Example 3 is not excessive, and reacts completely with the waste resin solvent containing vinyl ester resin, and cannot react with the modified separating agent. It can be seen from the data that the recovery rate of vinyl ester resin recovered in Example 1 is much higher than that of Comparative Examples 1-3, and the solution purity is higher, which fully proves the optimal effect achieved by the cooperation between the modified flocculant and the modified separating agent, and both are indispensable in the reaction process. And the recycling method provided by the present invention not only reduces the discharge of waste solvents, embodies environmental protection, but also reduces processing costs and improves the economic benefits of the enterprise.

[0040] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for recycling waste solvents from venous industrial resins, characterized in that: The following steps are involved: S1. Add 15-20 parts of a modified flocculant to 50-80 parts of a resin waste solvent containing a vinyl ester resin produced in the venous industry, and separate the mixture containing the vinyl ester resin by extraction; S2. The mixed solution containing the vinyl ester resin is filtered using an ultrafiltration membrane separation technique to obtain a vinyl ester resin mixed solution; S3. Add 1-3 parts of acetic acid to the vinyl ester resin mixture to adjust the pH and add 2-5 parts of a modified separating agent, and extract again to obtain a crude vinyl ester resin solution; S4. The crude vinyl ester resin is heated and distilled, and further purified to obtain a vinyl ester resin solution; The modified flocculant is prepared by the following steps: S101. Place 10-15 parts of polyoxypropyl glyceryl ether and 8-12 parts of xylene solution into a reaction vessel, mechanically stir for 3-5 minutes at a temperature of 90-150° C. to obtain a preliminary mixture; S102. The activated carbon was physically crushed with a hammer mill for 2-5 min, 5-10 parts of activated carbon and 20-25 parts of deionized water were mixed with the preliminary mixture and mechanically stirred to obtain a secondary mixture; S103. Add 3-6 parts of the modified liquid to the mixture of the second step, stir at 40-50° C. until a stable emulsion is formed to obtain a modified flocculant.

2. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: In step S2, the operating pressure of the ultrafiltration membrane separation technology is 0.2-0.4 MPa, and the molecular weight cutoff of the ultrafiltration membrane is 8000-12000 Daltons.

3. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: In step S2, acetic acid is used to adjust the pH value to a range of 6.4-6.

8.

4. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: In step S103, the modified liquid is a mixture of ammonium dihydrogen phosphate and polyferric phosphorus chloride in a mass ratio of 1-3:1.5-2.

5. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: In step S3, the preparation of the modified separating agent comprises the following steps: S201. Add 2-5 parts of sodium sulfide solution and 1-3 parts of xylene solution into a beaker and stir at a stirring speed of 300-500 r / min, a temperature of 30-40 ° C, and a reaction time of 5-10 min to obtain a preliminary mixed solution; S202. Add 0.5-2 parts of tetrahydrofuran solution and 10-15 parts of deionized water to the preliminary mixed solution and stir to obtain a modified separating agent.

6. The method for recycling waste solvent of venous industrial resin according to claim 5, characterized in that: In step S202, the stirring speed is 400-600 r / min, the temperature is 60-70° C., and the reaction time is 10-15 min.

7. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: The modified separation agent in step S3 also reacts with the excess modified flocculant in step S1.

8. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: The temperature of the heating distillation in step S4 is 90-100°C.

9. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: In step S102, the stirring speed is 400-500 r / min, and the reaction time is 5-8 min.

10. The method for recycling waste solvent of venous industrial resin according to claim 1, characterized in that: In step S103, the stirring speed is 450-550 r / min, and the reaction time is 15-20 min.

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