Claims for Patent: 10,143,972

Summary for Patent: 10,143,972

Title:	Ultrafiltration membrane and a preparation method thereof
Abstract:	The present invention provides an ultrafiltration membrane comprising a sulfone polymer membrane matrix with pores and an organic polymer sealing layer, wherein the pores are filled with nanoadsorbents. The present invention further provides a method for preparing the ultrafiltration membrane, which includes the following steps: (1) synthesizing nanoadsorbents; (2) preparing the sulfone polymer membrane matrix by immersion-precipitation phase inversion; and (3) immobilizing nanoadsorbents in the pores of the sulfone polymer membrane matrix by reverse filling, then sealing the pores with organic polymers to form a multifunctional ultrafiltration membrane. In the present invention, colloidal gold, polyethylene glycol molecules and Pb(II) ions (and so forth) are utilized as models of viruses, macromolecular organic pollutants, and small molecular pollutants, respectively. It is shown that the multifunctional ultrafiltration membrane allows for removal of multiple pollutants from water and can simultaneously remove multiple pollutants under low pressure.
Inventor(s):	Li; Jiansheng (Jiangsu, CN), Pan; Shunlong (Jiangsu, CN), Fang; Xiaofeng (Jiangsu, CN), Wang; Lianjun (Jiangsu, CN), Sun; Xiuyun (Jiangsu, CN), Shen; Jinyou (Jiangsu, CN), Han; Weiqing (Jiangsu, CN), Liu; Xiaodong (Jiangsu, CN)
Assignee:	NANJING UNIVERSITY OF SCIENCE AND TECHNOLOGY (Jiangsu, CN)
Application Number:	15/540,260
Patent Claims:	1. A method for preparing an ultrafiltration membrane, the ultrafiltration membrane comprising a sulfone polymer membrane matrix with pores and an organic polymer sealing layer, wherein the pores are filled with nanoadsorbents, the nanoadsorbents are porous hollow nanoparticles, and the porous hollow nanoparticles are hollow porous hydrous zirconium oxide (HZO) particles, the method comprising the following steps: (1) synthesizing the nanoadsorbents; (2) preparing the sulfone polymer membrane matrix by immersion-precipitation phase inversion, wherein the sulfone polymer membrane matrix has a top surface and a bottom surface opposite to each other, the pores extend from the bottom surface of the sulfone polymer membrane matrix toward the top surface of the sulfone polymer membrane matrix; and (3) immobilizing the nanoadsorbents in the pores of the sulfone polymer membrane matrix by filling the nanoadsorbents into the pores from the bottom surface of the sulfone polymer membrane matrix, then sealing the pores with organic polymers to form the ultrafiltration membrane. 2. The method according to claim 1, wherein a procedure of the immersion-precipitation phase inversion comprises the following steps: (1) stirring sulfone polymers, polyvinylpyrrolidone and N--N dimethylformamide constantly in oil bath to obtain a uniform and homogeneous casting solution, then leaving the casting solution to stand to remove remaining air bubbles, and spreading the bubbleless casting solution with a casting knife onto a clean glass plate of which a temperature is 60.about.100.degree. C. to form a membrane; (2) standing the glass plate in air for evaporation and then immersing it in a non-solvent bath; and (3) taking out the resulting membrane and rinsing it in deionized water to obtain the sulfone polymer membrane matrix which is then kept in deionized water before use, wherein the procedure of filling the nanoadsorbents into the pores from the bottom surface of the sulfone polymer membrane matrix comprises the following steps: (1) dispersing the synthesized nanoadsorbents in water by ultrasound to form a nanoadsorbent solution; and (2) placing the bottom surface of the sulfone polymer membrane matrix upside down in a stirred ultrafiltration cell in order that the bottom of the sulfone polymer membrane matrix is facing the filtrated nanoadsorbent solution and filling the polymer membrane matrix with the filtrated nanoadsorbent solution under controlled pressure, wherein the pressure ranges from 0.01 Mpa to 0.1 Mpa. 3. The method according to claim 1, wherein the pores are finger-like in shape. 4. The method according to claim 1, wherein the pore sizes are 10.about.40 .mu.m.times.90.about.150 .mu.m. 5. The method according to claim 1, wherein the porosity of the ultrafiltration membrane is 65%.about.80% before the pores are filled with the nanoadsorbents and 35%.about.50% after the pores are filled with the nanoadsorbents. 6. The method according to claim 1, wherein a content of the nanoadsorbents is 10%.about.70%. 7. The method according to claim 1, wherein the organic polymers are polydopamine or polyvinyl alcohol. 8. The method according to claim 2, wherein the sulfone polymers are polysulfone and polyethersulfone.