阅读说明：本技术 一种超滤膜的涂层工艺 (Coating process of ultrafiltration membrane ) 是由 陈泉学 于 2019-08-28 设计创作，主要内容包括：本发明提出了一种超滤膜的涂层工艺,所述工艺包括,制备改性几丁聚糖,通过改性几丁聚糖的水溶液对超滤膜进行预涂改性,将预涂改性的超滤膜置于表面活性剂中进行接枝改性,利用紫外线照射进行活化和接枝后,冲洗干燥得到超滤膜,本发明的工艺所制备的超滤膜具有良好的水通量和重金属离子吸附性能,具有良好的应用前景。(The invention provides a coating process of an ultrafiltration membrane, which comprises the steps of preparing modified chitosan, performing precoating modification on the ultrafiltration membrane by using an aqueous solution of the modified chitosan, placing the precoated modified ultrafiltration membrane in a surfactant for grafting modification, activating and grafting by using ultraviolet irradiation, and washing and drying to obtain the ultrafiltration membrane.)

1. a coating process of an ultrafiltration membrane is characterized by comprising the following steps:

Step one, adding modified chitosan into deionized water, and enabling the deionized water containing the modified chitosan to pass through an ultrafiltration membrane to obtain a precoated ultrafiltration membrane;

Step two, placing the precoated ultrafiltration membrane into a surfactant for soaking for 1-2min, and keeping ultraviolet illumination for 5-10min under the soaking condition to obtain a pretreated ultrafiltration membrane;

and step three, placing the pretreated ultrafiltration membrane in a deionized water tank, performing back washing and forward washing on the ultrafiltration membrane by using deionized water, and drying to obtain the ultrafiltration membrane with the surface coating after washing.

2. The process of coating an ultrafiltration membrane according to claim 1, wherein the modified chitosan is prepared by a method comprising: heating maleic anhydride to a molten state, adding chitosan into the molten maleic anhydride, keeping the temperature, stirring, reacting for 5-10min, and cooling to normal temperature to obtain the modified chitosan.

3. The process for coating an ultrafiltration membrane according to claim 2, wherein the maleic anhydride: the mass ratio of the chitosan is (2-5): 1.

4. the process for coating ultrafiltration membranes according to claim 2, wherein the temperature of the heated maleic anhydride is 60-65 ℃.

5. The process of coating an ultrafiltration membrane of claim 1, wherein in step one, the deionized water containing the modified chitosan is passed through the ultrafiltration membrane at a pressure of 0.2 to 0.4 Mpa.

6. The process for coating an ultrafiltration membrane according to claim 1, wherein in step one, the deionized water: the mass ratio of the modified chitosan is (20-40): 1.

7. The process for coating an ultrafiltration membrane according to claim 1, wherein said surfactant is one of monolauryl phosphate, potassium laureth phosphate and coconut monoethanolamide.

8. the process for coating the ultrafiltration membrane according to claim 1, wherein in the second step, the irradiation intensity of the ultraviolet light is 500-1000W/m ².

9. the process for coating an ultrafiltration membrane according to claim 1, wherein said ultrafiltration membrane is a polysulfone ultrafiltration membrane or a polyethersulfone ultrafiltration membrane.

10. the process for coating an ultrafiltration membrane of claim 1, wherein 25 to 50ml of the modified chitosan solution is required per square centimeter of the ultrafiltration membrane.

Technical Field

the invention relates to the technical field of sewage treatment equipment, in particular to a coating process of an ultrafiltration membrane.

Background

The filtration of the ultrafiltration membrane is far away from the mechanical screening of the fused particles passing through the membrane surface, the traditional ultrafiltration membrane can only filter and screen macromolecular particles from a few nanometers to dozens of nanometers, and heavy metal ions cannot be effectively screened.

at present, functional groups with a heavy metal ion adsorption function are grafted on the surface of an ultrafiltration membrane which is common and has a heavy metal ion filtration function, the preparation method is relatively complex, the prepared ultrafiltration membrane with the heavy metal ion adsorption function has more limitations on other functions, the preparation cost is high, and the commercial application value is low.

Disclosure of Invention

In view of the above, the invention provides a coating process of an ultrafiltration membrane, which is simple in method and lower in cost.

The technical scheme of the invention is realized as follows: the invention provides a coating process of an ultrafiltration membrane, which comprises the following steps:

Step one, adding modified chitosan into deionized water, and enabling the deionized water containing the modified chitosan to pass through an ultrafiltration membrane to obtain a precoated ultrafiltration membrane;

Step two, placing the precoated ultrafiltration membrane into a surfactant for soaking for 1-2min, and keeping ultraviolet illumination for 5-10min under the soaking condition to obtain a pretreated ultrafiltration membrane;

And step three, placing the pretreated ultrafiltration membrane in a deionized water tank, performing back washing and forward washing on the ultrafiltration membrane by using deionized water, and drying to obtain the ultrafiltration membrane with the surface coating after washing.

On the basis of the technical scheme, preferably, the preparation method of the modified chitosan comprises the following steps: heating maleic anhydride to a molten state, adding chitosan into the molten maleic anhydride, keeping the temperature, stirring, reacting for 5-10min, and cooling to normal temperature to obtain the modified chitosan.

On the basis of the above technical scheme, preferably, the ratio of maleic anhydride: the mass ratio of the chitosan is (2-5): 1.

On the basis of the technical scheme, the temperature for heating the maleic anhydride is preferably 60-65 ℃.

more preferably, in the first step, the pressure of the deionized water containing the modified chitosan is 0.2-0.4MPa when the deionized water is passed through the ultrafiltration membrane.

On the basis of the above technical solution, preferably, in the step one, the deionized water: the mass ratio of the modified chitosan is (20-40): 1.

On the basis of the technical scheme, preferably, the surfactant is one of monolauryl phosphate, potassium lauryl alcohol ether phosphate and coconut monoethanolamide.

Based on the above technical solution, preferably, in the second step, the irradiation intensity of the ultraviolet light is 500-1000W/m 2.

On the basis of the technical scheme, preferably, the ultrafiltration membrane is a polysulfone ultrafiltration membrane or a polyethersulfone ultrafiltration membrane.

Based on the technical scheme, preferably, 25-50ml of modified chitosan solution is required for each square centimeter of ultrafiltration membrane.

compared with the prior art, the coating process of the ultrafiltration membrane has the following beneficial effects:

(1) The ultrafiltration membrane coating process modifies the ultrafiltration membrane, membrane pores and the surface of the ultrafiltration membrane are pre-coated by the modified chitosan, so that the adsorption performance of heavy metal ions is enhanced, meanwhile, the surface of the ultrafiltration membrane is modified again by adopting the surface modifier, so that the hydrophilic performance of the ultrafiltration membrane is enhanced, the water flux and the anti-pollution capacity are improved, the grafting strength of the pre-coating modification is enhanced, and the grafting is more stable by ultraviolet irradiation under the grafting and soaking conditions;

(2) The ultrafiltration membrane treated by the ultrafiltration membrane coating process disclosed by the invention reserves the strength of a conventional ultrafiltration membrane substrate, has higher water flux and heavy metal ion absorption performance, and has a good application prospect.

Detailed Description

the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.