Production method of high-efficiency ion exchange membrane

Abstract

The invention provides a production method of a high-effect ion exchange membrane, and relates to the technical field of membrane materials. The production method of the high-efficiency ion exchange membrane comprises the following steps: S1, mixing cationic resin powder, anionic resin powder and modified high-density polyethylene; s2, putting the mixed material into a closed mixer for mixing; s3, cutting the mixed bulk material into a particle material; and S4, performing melt extrusion on the particle material, and cutting into slices. The content of ion exchange resin powder in the membrane is increased, the loss amount of ion exchange resin active groups in the high-temperature manufacturing process of the membrane is reduced, the ion exchange capacity of the ion exchange membrane is further improved, meanwhile, the antioxidant and the anti-aging agent reduce the failure ratio of the active groups in the high-temperature preparation process of the ion exchange resin, and the service life of the membrane is prolonged. And the crosslinking degree of the diaphragm base material is improved by adding the crosslinking agent, so that the overall strength of the diaphragm is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of diaphragm materials, in particular to a production method of high-efficiency ion exchange membrane. BACKGROUND

[0002] Ion exchange membrane is a kind of high molecular film containing ion groups and having selective permeability to ions in solution. This kind of membrane is usually composed of high molecular material containing fixed ion groups and can transfer ions in aqueous solution. Ion exchange membrane is widely used in electrolytic cell, fuel cell, electrodialysis, electrolyte membrane, water treatment and other fields involving ion transfer. The function of these membranes is to allow specific ions to pass through while preventing the passage of the rest of the substances, thereby realizing the selective transfer of ions.

[0003] The exchange capacity of ion exchange membrane on the market is 1.8 mol / kg at present, and the water resistivity of the product can reach 16 megaohms in the application of electric desalination device. It takes a long time to raise the water resistivity to 16 megaohms, and the quality of product water decreases rapidly in the case of high ion content in source water. In order to improve the ion exchange capacity, the resin powder content is usually increased to improve the efficiency of ion exchange membrane. However, the strength of the membrane sheet decreases obviously after the powder ratio is increased. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a production method of high-efficiency ion exchange membrane, which solves the problems of low ion exchange capacity of traditional ion exchange membrane and obvious decrease in the strength of the membrane sheet after increasing the resin powder content.

[0005] To achieve the above object, the present application is implemented by the following technical scheme: a production method of high-efficiency ion exchange membrane, comprising the following steps:

[0006] S1. Pre-mixing

[0007] The cationic resin powder, anionic resin powder and modified high-density polyethylene are weighed according to the proportion and then put into a high-speed mixing stirrer to mix uniformly at room temperature at a speed of 2000-3000 r / min to obtain a mixture;

[0008] S2. Mixing

[0009] The mixture is put into a closed mixer, the cavity is heated to 160-170 DEG C by a heating device in the closed mixing chamber, the mixture is fully mixed in the viscous flow state by the rotation of the rotor in the mixing chamber, and the mixing is continued for 30-60 min after the addition of an additive into the mixer during the mixing process;

[0010] S3. Cutting

[0011] After the material of the lump-shaped body after the mixing is taken out from the mixing machine, the material is first cut into small pieces with a length of 5-8 cm and a width of 5-8 cm by using a slitting machine, and the small pieces are cooled by standing, and then the small pieces are crushed into granular materials with a particle size of less than 5 mm by using a blade-type crusher.

[0012] S4. Extruding the film

[0013] The crushed granular materials are put into an extruder, and the inner cavity of the extruder is heated to 185-220 DEG C, and the granular materials are in a molten state and are extruded in the temperature range, and are extruded into a film with a width of 400-450 mm and a thickness of 0.6 mm, and the extruded film is cooled by calendering and then is stretched by traction, and finally the film is cut into pieces according to the size by using a film cutting machine.

[0014] Preferably, the weight ratio of the raw materials in the ion exchange film is (cationic resin powder + anionic resin powder): modified high-density polyethylene: additive = (60-80):(15-35):5.

[0015] Preferably, the additive comprises a plasticizer, an antioxidant, an anti-aging agent, a paraffin and a crosslinking agent, and the weight ratio of the plasticizer, the antioxidant, the anti-aging agent, the paraffin and the crosslinking agent is (5-10):(0.5-1):(0.5-1):(1-5).

[0016] Preferably, the plasticizer is any one or a combination of polytetrafluoroethylene sulfonate, polyether sulfone, polyamide, polyvinyl alcohol and polyurethane; the antioxidant is 2,6-di-tert-butyl-4-methylphenol or tris(3,5-di-tert-butyl-4-hydroxyphenyl)butene; the anti-aging agent is 2-hydroxy-4-methylbenzoic acid butyl ester or a benzodiketone compound; and the crosslinking agent is any one or a combination of diethylene triamine, triethylene tetramine, ethylene oxide and propylene oxide.

[0017] The application provides a production method of a high-efficiency ion exchange film.

[0018] 1. The application first increases the content of ion exchange resin powder in the film, reduces the loss of active groups of the ion exchange resin in the high-temperature preparation process of the film, and thus improves the ion exchange capacity of the ion exchange film, thereby improving the efficiency of the ion exchange film; meanwhile, the antioxidant and the anti-aging agent are added to the raw materials to reduce the failure rate of the active groups of the ion exchange resin in the high-temperature preparation process, and the crosslinking agent is added to improve the crosslinking degree of the film substrate, thereby improving the overall strength of the film. DETAILED DESCRIPTION

[0019] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0020] Embodiment one:

[0021] The embodiment of the present application provides a production method of a high-efficiency ion exchange membrane, comprising the following steps:

[0022] S1. Pre-mixing

[0023] After the cationic resin powder, the anionic resin powder and the modified high-density polyethylene are weighed according to the proportion, the mixture is obtained by uniformly mixing the powders in a high-speed mixing stirrer at room temperature at a rotating speed of 2000 r / min;

[0024] S2. Mixing

[0025] After the mixture is put into a closed mixer, the cavity is heated to 160 DEG C by a heating device in a closed mixing chamber, and the mixture is fully mixed in a viscous flow state by the rotation of a rotor in the mixing chamber. After the additive is added to the mixer during the mixing process, the mixing is continued for 30 min;

[0026] S3. Cutting

[0027] After the dough-like material after mixing is taken out of the mixer, the material is first cut into small pieces with a length and a width of 5 cm by using a cutting machine. After the small pieces are cooled, the small pieces are crushed into granular materials with a particle size of less than 5 mm by using a blade-type crusher;

[0028] S4. Extruding and cutting

[0029] After the crushed granular material is put into an extruder, the cavity of the extruder is heated to 185 DEG C. The granular material is in a molten state and is extruded at the temperature interval. The extruded sheet has a width of 400 mm and a thickness of 0.6 mm. After the extruded sheet is calendered and cooled, the sheet is stretched by traction, and finally the sheet is cut into pieces according to the size by using a sheet cutting machine.

[0030] The weight ratio of the raw materials in the ion exchange membrane is (cationic resin powder + anionic resin powder): modified high-density polyethylene: additive = 60:35:5. By increasing the content of ion exchange resin powder in the membrane, the loss of active groups of ion exchange resin during the high-temperature production process of the membrane is reduced, and the ion exchange capacity of the ion exchange membrane is improved, thereby improving the efficiency of the ion exchange membrane.

[0031] The additives include plasticizers, antioxidants, anti-aging agents, paraffin and cross-linking agents, and the weight ratio of the plasticizers, antioxidants, anti-aging agents, paraffin and cross-linking agents is 10:1:1:5. The antioxidants and anti-aging agents are further added to the raw materials to reduce the failure rate of active groups of the ion exchange resin in the process of preparation at high temperature, and the cross-linking agent is added to improve the cross-linking degree of the membrane base material, so as to improve the overall strength of the membrane.

[0032] The plasticizer is any one or a combination of polytetrafluoroethylene sulfonate, polyether sulfone, polyamide, polyvinyl alcohol and polyurethane, the polytetrafluoroethylene sulfonate can increase the mechanical strength and chemical stability of the membrane, the polyether sulfone is used to enhance the high temperature resistance and mechanical strength of the membrane, the polyamide is used to support the layer, increase the structural strength and stability of the membrane, the polyvinyl alcohol can improve the softness and tensile properties of the membrane, and the polyurethane can improve the flexibility and corrosion resistance of the membrane; the antioxidant is 2,6-di-tert-butyl-4-methylphenol or tri(3,5-di-tert-butyl-4-hydroxyphenyl) butene; the anti-aging agent is 2-hydroxy-4-methylbenzoic acid butyl ester or benzodiketone compound; the addition of the antioxidant and the anti-aging agent can not only reduce the failure rate of active groups of the ion exchange resin in the process of preparation at high temperature, but also improve the ultraviolet resistance and oxidation resistance of the membrane, effectively prolong the service life of the membrane, and the cross-linking agent is any one or a combination of diethylene triamine, triethylene tetramine, ethylene oxide and propylene oxide.

[0033] Example two:

[0034] The embodiment of the application provides a production method of a high-efficiency ion exchange membrane, which comprises the following steps:

[0035] S1. Pre-mixing

[0036] The cation resin powder, the anion resin powder and the modified high-density polyethylene are weighed according to the proportion, and then are put into a high-speed mixing stirrer to be uniformly mixed at room temperature at a rotating speed of 3000 r / min to obtain a mixed material;

[0037] S2. Mixing

[0038] The mixed material is put into a closed mixer, the heating device is used to heat the cavity to 170 DEG C in the closed mixing chamber, the rotation of the rotor in the mixing chamber is used to fully mix the mixed material in the viscous flow state, and the additives are continuously added to the mixer in the mixing process, and then the mixing is continuously carried out for 60 min.

[0039] S3. Cutting

[0040] After the material of the lump-shaped body after mixing is taken out of the mixing machine, the material is first cut into small pieces with a length and width of 8 cm using a slitting machine. The cut small pieces are left to cool, and after cooling, the small pieces are crushed into granular material with a particle size of less than 5 mm using a blade crusher;

[0041] S4. Extruding the cutting piece

[0042] The crushed granular material is put into an extruder, and the inner cavity of the extruder is heated to 220°C. The granular material is in a molten state in this temperature range and is extruded. The extruded sheet has a width of 450 mm and a thickness of 0.6 mm. The extruded sheet film material is cooled after calendering and then stretched by traction. Finally, the sheet film material is cut into pieces according to the size by a cutting machine.

[0043] The weight ratio of the raw materials in the ion exchange membrane piece is (cationic resin powder + anionic resin powder): modified high-density polyethylene: additive = 80:15:5. By increasing the content of ion exchange resin powder in the membrane piece, the loss of active groups of ion exchange resin during high-temperature preparation of the membrane piece is reduced, thereby improving the ion exchange capacity of the ion exchange membrane and the efficiency of the ion exchange membrane.

[0044] The additive includes a plasticizer, an antioxidant, an anti-aging agent, a paraffin, and a cross-linking agent, and the weight ratio of the plasticizer, the antioxidant, the anti-aging agent, the paraffin, and the cross-linking agent is 5:0.5:0.5:1. The addition of the antioxidant and the anti-aging agent in the raw materials reduces the failure rate of the active groups of the ion exchange resin during high-temperature preparation, and the addition of the cross-linking agent improves the cross-linking degree of the membrane piece substrate, thereby improving the overall strength of the membrane piece.

[0045] The plasticizer is any one or a combination of polytetrafluoroethylene sulfonate, polyether sulfone, polyamide, polyvinyl alcohol, and polyurethane. The polytetrafluoroethylene sulfonate can increase the mechanical strength and chemical stability of the membrane piece. The polyether sulfone is used to enhance the high-temperature resistance and mechanical strength of the membrane. The polyamide is used to support the layer, increase the structural strength and stability of the membrane, and the polyvinyl alcohol can improve the softness and tensile properties of the membrane. The polyurethane can improve the flexibility and corrosion resistance of the membrane. The antioxidant is 2,6-di-tert-butyl-4-methylphenol or tris(3,5-di-tert-butyl-4-hydroxyphenyl)butene. The anti-aging agent is 2-hydroxy-4-methylbenzoic acid butyl ester or benzodiketone compound. The addition of the antioxidant and the anti-aging agent not only reduces the failure rate of the active groups of the ion exchange resin during high-temperature preparation, but also improves the ultraviolet resistance and oxidation resistance of the membrane, effectively prolonging the service life of the membrane. The cross-linking agent is any one or a combination of diethylene triamine, triethylene tetramine, ethylene oxide, and propylene oxide.

[0046] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. A method for producing a high performance ion exchange membrane, characterized by: The method comprises the following steps: S1. Pre-mixing The cationic resin powder, anionic resin powder and modified high-density polyethylene are weighed in proportion and then put into a high-speed mixing stirrer to mix uniformly at room temperature at a speed of 2000-3000 r / min to obtain a mixture; S2. Mixing The mixture is put into a closed mixer, and the cavity is heated to 160-170℃ by a heating device in a closed mixing chamber. The mixture is fully mixed in a viscous flow state by the rotation of the rotor in the mixing chamber. After the additives are added to the mixer during the mixing process, the mixing is continued for 30-60 min; S3. Cutting The mixed material is taken out of the mixer and cut into small pieces with a length and width of 5-8 cm using a cutting machine. The cut small pieces are cooled and then crushed into granular materials with a particle size of less than 5 mm using a blade crusher; S4. Extruding and cutting The crushed granular material is put into an extruder, and the cavity of the extruder is heated to 185-220℃. The granular material is in a molten state and is extruded at this temperature range. The extruded sheet has a width of 400-450 mm and a thickness of 0.6 mm. The extruded sheet is cooled by calendering and then stretched by traction. Finally, the sheet is cut into pieces according to the size by a cutting machine.

2. The method of claim 1, wherein the method further comprises: The weight ratio of the raw materials in the ion exchange membrane sheet is (cationic resin powder + anionic resin powder) : modified high-density polyethylene : additives = (60-80) : (15-35) :

5.

3. The method of claim 1, wherein the method further comprises: The additives include plasticizers, antioxidants, anti-aging agents, paraffin and cross-linking agents, and the weight ratio of the plasticizers, antioxidants, anti-aging agents, paraffin and cross-linking agents is (5-10) : (0.5-1) : (0.5-1) : (1-5). ​ 4. The method of claim 3, wherein the method further comprises the step of: 5 The plasticizer is any one or a combination of polytetrafluoroethylene sulfonate, polyether sulfone, polyamide, polyvinyl alcohol and polyurethane; the antioxidant is 2,6-di-tert-butyl-4-methylphenol or tris(3,5-di-tert-butyl-4-hydroxyphenyl) butene; the anti-aging agent is 2-hydroxy-4-methylbenzoic acid butyl ester or benzodiketone compound; and the cross-linking agent is any one or a combination of diethylene triamine, triethylene tetramine, oxirane and propylene oxide.