阅读说明：本技术 一种兼具耐高温及耐有机溶剂阳离子交换膜的制备方法 (Preparation method of cation exchange membrane with high temperature resistance and organic solvent resistance ) 是由 赵严 沈江南 沈鹏鑫 王利祥 于 2019-09-16 设计创作，主要内容包括：本发明公开了一种阳离子的交换膜的制备方法,其包括如下步骤：(1)将KAN材料、强碱与二甲基亚砜溶剂按照质量百分比0.5％～10％：1％～20％：70％～99％混合,并加入质量用量为KAN材料质量用量的1％～400％的2,5-邻磺酸对苯二胺单体,并密封搅拌,于30～90℃反应3-10天后,再将温度控制在20-30℃继续搅拌18-48h,得到铸膜液,并在水平放置的干燥玻璃板或者网布上刮制成膜；(2)将刮制得到的膜立即浸入EDC-HCl和NHS的混合水溶液中,相转换完成后,再将该膜浸入至新配制的EDC-HCl和NHS的混合水溶液中并密封,反应1-5天后将膜进行干燥,得到阳离子交换膜。本发明制备工艺简便,操作易行,无毒环保；制备的阳离子交换膜兼具耐高温和耐有机溶剂性能。(The invention discloses a preparation method of a cation exchange membrane, which comprises the following steps: (1) the KAN material, strong base and dimethyl sulfoxide solvent are mixed according to the mass percentage of 0.5-10%: 1% -20%: 70-99 percent of the raw materials are mixed, 2, 5-o-sulfonic acid p-phenylenediamine monomer with the mass amount of 1-400 percent of the mass amount of KAN material is added, the mixture is sealed and stirred, after the mixture reacts for 3-10 days at the temperature of 30-90 ℃, the mixture is continuously stirred for 18-48 hours at the temperature of 20-30 ℃ to obtain casting film liquid, and the casting film liquid is scraped into a film on a horizontally placed dry glass plate or a mesh; (2) and immediately immersing the scraped membrane into a mixed aqueous solution of EDC-HCl and NHS, after phase conversion is finished, immersing the membrane into a newly prepared mixed aqueous solution of EDC-HCl and NHS, sealing, reacting for 1-5 days, and drying the membrane to obtain the cation exchange membrane. The preparation process is simple and convenient, the operation is easy, and the preparation method is non-toxic and environment-friendly; the prepared cation exchange membrane has the performances of high temperature resistance and organic solvent resistance.)

1. A preparation method of a cation exchange membrane comprises the following steps:

(1) the KAN material, strong base and dimethyl sulfoxide solvent are mixed according to the mass percentage of 0.5-10%: 1% -20%: 70-99 percent of the raw materials are mixed, 2, 5-o-sulfonic acid p-phenylenediamine monomer with the mass amount of 1-400 percent of the mass amount of KAN material is added, the mixture is sealed and stirred, after the mixture reacts for 3-10 days at the temperature of 30-90 ℃, the mixture is continuously stirred for 18-48 hours at the temperature of 20-30 ℃ to obtain casting film liquid, and the casting film liquid is scraped into a film on a horizontally placed dry glass plate or a mesh;

(2) immediately immersing the scraped membrane into a mixed aqueous solution of 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide hydrochloride and N-hydroxysuccinimide, after phase conversion is finished, immersing the membrane into a newly prepared mixed aqueous solution of 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide hydrochloride and N-hydroxysuccinimide, sealing, reacting for 1-5 days, and drying the membrane to obtain a cation exchange membrane;

in the mixed aqueous solution of the 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide salt and the N-hydroxysuccinimide, the concentrations of the 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide salt and the N-hydroxysuccinimide are 0.1-5 g/L and 0.1-5 g/L respectively.

2. The method of claim 1, wherein: in the step (1), the strong base is lithium hydroxide, sodium hydroxide or potassium hydroxide.

3. The method of claim 1 or 2, wherein: the KAN material, the strong base and the dimethyl sulfoxide solvent are as follows by mass percent: 2% -5%: 4% -8%: 87 to 93 percent.

4. The method of claim 1 or 2, wherein: the mass consumption of the 2, 5-o-sulfonic acid p-phenylenediamine is 20-200% of the mass consumption of the KAN material.

5. The method of claim 4, wherein: the mass consumption of the 2, 5-o-sulfonic acid p-phenylenediamine is 100% of the mass consumption of the KAN material.

6. The method of claim 1 or 2, wherein: in the step (1), the reaction conditions are as follows: stirring at 60-90 deg.C for 3-5 days, and stirring at 20-30 deg.C for 1-2 days.

7. The method of claim 6, wherein: in the step (1), the reaction conditions are as follows: the mixture was stirred at 70 ℃ for 3 days and then at 25 ℃ for 24 hours.

8. The method of claim 1 or 2, wherein: in the step (1), the conditions for scraping the film are as follows: the environment temperature is 10-50 ℃, the humidity is kept at 5% -50%, and the thickness of the film scraping knife is 50-500 mu m.

9. The method of claim 1 or 2, wherein: in the step (2), the drying temperature is 45-80 ℃.

10. The method of claim 1 or 2, wherein: in the step (2), in the mixed aqueous solution of the 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide salt and the N-hydroxysuccinimide, the concentrations of the 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide salt and the N-hydroxysuccinimide are 1g/L and 0.6g/L respectively.

Technical Field

The invention relates to a preparation method of a cation exchange membrane with high temperature resistance and organic solvent resistance.

Technical Field

With the rapid progress of science and technology, great attention has been paid to the development of advanced composite membranes for ion energy extraction or high-purity organic solvent ion removal in high-technology industrial production. In particular, ion exchange membranes, which are the core elements of electrodialysis, have unique advantages over other pressure driven membranes in ion desalination or concentration of ions in high concentrations of brine.

The ion exchange membranes are mainly divided into anion exchange membranes and cation exchange membranes, which are widely applied to desalination, salt concentration, salt extraction and other processes, but with the development of science and technology, the traditional ion exchange membrane materials cannot meet the increasingly updated industrial requirements due to the limitation of complex components of water environment. For example, a small amount of salt contained in an organic solvent solution may cause a great influence on device performance during the process of preparing a high-end and high-precision scientific and technological material device by using organic solvent etching; the steel wastewater contains a large amount of metal cations to be removed, and the like. Therefore, the search and design of suitable materials for preparing high temperature resistant and organic solvent resistant separation membranes has become an urgent development requirement.

The Kevlar nanofiber is an ultra-tough material and is widely applied to aerospace, bullet-proof vest manufacturing, high-temperature-resistant and organic corrosion-resistant protective clothing and the like. Due to hydrogen bonds, intermolecular pi-pi bonds and the like existing between the Kevlar nano fibers, the material shows excellent thermal stability and organic solvent resistance. Therefore, the material can be considered to be designed and applied to an ion exchange membrane material.

Disclosure of Invention

The invention aims to provide a preparation method of a cation exchange membrane with high temperature resistance and organic solvent resistance.

The invention is realized by the following technical scheme:

a preparation method of a cation exchange membrane comprises the following steps:

(1) the KAN material, strong base and dimethyl sulfoxide solvent are mixed according to the mass percentage of 0.5-10%: 1% -20%: 70-99 percent of the raw materials are mixed, 2, 5-o-sulfonic acid p-phenylenediamine (DSA) monomer with the mass amount of 1-400 percent of the mass amount of KAN material is added, the mixture is sealed and stirred, after the mixture reacts for 3-10 days at the temperature of 30-90 ℃, the temperature is controlled to be 20-30 ℃ and the mixture is continuously stirred for 18-48 hours, so as to obtain casting film liquid, and the casting film liquid is scraped to form a film on a horizontally placed dry glass plate or mesh;

(2) immediately immersing the scraped membrane into a mixed aqueous solution of 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide hydrochloride (EDC-HCl) and N-hydroxysuccinimide (NHS), after phase conversion is finished, immersing the membrane into a newly prepared mixed aqueous solution of 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide hydrochloride and N-hydroxysuccinimide, sealing, reacting for 1-5 days, and drying the membrane to obtain a cation exchange membrane;

in the mixed aqueous solution of the 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide salt and the N-hydroxysuccinimide, the concentrations of the 1-ethyl-3- (3-dimethylamine-nitrosyl) carbodiimide salt and the N-hydroxysuccinimide are 0.1-5 g/L (preferably 1g/L) and 0.1-5 g/L (preferably 0.6g/L), respectively.

According to the invention, by utilizing the characteristics of high temperature resistance and organic solvent resistance of Kevlar aramid nano-fiber (KAN) materials and combining an amide hydrolysis reaction and an amide condensation reaction, a 2,5-Diaminobenzene Sulfonic Acid (DSA) monomer is introduced into the KAN material structure, so that the cation exchange membrane with high temperature resistance and organic solvent resistance is prepared.

In the invention, the KAN material can be aramid nano-fiber of AP, K29, K49, 100, 119, 129, KM2, KM2 Plus and the like. The structure of the DSA monomer is shown below:

preferably, in step (1), the strong base is lithium hydroxide, sodium hydroxide or potassium hydroxide.

Preferably, the KAN material, the strong base and the dimethyl sulfoxide solvent are as follows by mass percent: 2% -5%: 4% -8%: 87 to 93 percent.

Preferably, the mass amount of the 2, 5-o-sulfonic para-phenylenediamine (DSA) is 20 to 200 percent of the mass amount of the KAN material, and the most preferred is 100 percent.

Preferably, in the step (1), the reaction conditions are as follows: stirring at 60-90 deg.C for 3-5 days, and stirring at 20-30 deg.C for 1-2 days. More preferably, the mixture is stirred at 70 ℃ for 3 days and then at 25 ℃ for 24 hours.

Preferably, in the step (1), the conditions for scraping the film are as follows: the environment temperature is 10-50 ℃, the humidity is kept at 5% -50%, and the thickness of the film scraping knife is 50-500 mu m.

Preferably, in the step (2), the drying temperature is 45-80 ℃.

Compared with the prior art, the invention has the beneficial effects that: the preparation process is simple and convenient, the operation is easy, and the preparation method is non-toxic and environment-friendly; the prepared cation exchange membrane has the performances of high temperature resistance and organic solvent resistance.

Drawings

FIG. 1 is a chemical structure of Kevlar nano-fiber selected by the invention;

FIG. 2 is the ion exchange capacity of four cation exchange membranes prepared by the present invention, which shows that the ion exchange capacity is increased with the increase of the DSA dosage;

FIG. 3 shows the water content of four cation exchange membranes prepared by the present invention, which is seen that the water content increases with the increase of the DSA dosage;

FIG. 4 is the surface resistance of four cation exchange membranes prepared according to the present invention, which shows that the surface resistance of the membranes decreases with the increase of the dosage of DSA;

FIG. 5 is a scanning electron microscope image of the surfaces of four cation exchange membranes prepared by the present invention;

FIG. 6 is a schematic view of an electrodialysis process according to the invention;

FIG. 7 shows KAN # DSA-100% cation exchange membrane pair Li prepared by the present invention ₂SO ₄Desalination efficiency and concentration efficiency;

FIG. 8 shows KAN # DSA-100% cation exchange membrane pair (NH) prepared by the present invention ₄) ₂SO ₄Desalination efficiency and concentration efficiency;

FIG. 9 shows KAN # DSA-100% cation exchange membrane vs MgSO prepared by the present invention ₄Desalination efficiency and concentration efficiency;

FIG. 10 shows the high temperature resistance test of KAN # DSA-100% cation exchange membrane prepared by the present invention;

FIG. 11 shows the performance test of KAN # DSA-100% cation exchange membrane prepared by the present invention for organic solvent resistance.

Detailed Description

The invention is described in further detail below with reference to the following figures and embodiments: