Anti-pollution composite reverse osmosis membrane and preparation method thereof

A reverse osmosis membrane, anti-pollution technology, applied in semi-permeable membrane separation, chemical instruments and methods, osmosis/dialysis water/sewage treatment, etc., can solve problems such as short travel

Active Publication Date: 2021-06-01
中化(宁波)润沃膜科技有限公司
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] Aiming at the key problems affecting industrialization such as multi-step and time-consuming in the existing reverse osmosis membrane surface modification technology, the present invention proposes to combine tannic acid and poly The aqueous solution of vinyl alcohol is used as the coating solution, which can be applied to the surface of the polyamide reverse osmosis membrane by one-step method, the stroke is short, and the process is simple and easy for industrial operation

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Anti-pollution composite reverse osmosis membrane and preparation method thereof
  • Anti-pollution composite reverse osmosis membrane and preparation method thereof
  • Anti-pollution composite reverse osmosis membrane and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0082] In some embodiments, the preparation method of the composite reverse osmosis membrane of the present invention comprises the following steps:

[0083] (1) Add polyvinyl alcohol or its aqueous solution to the tannic acid aqueous solution, stir evenly, optionally adjust the pH to 3-6, and obtain the mass ratio of polyvinyl alcohol and tannic acid as (5-500): 1 coating solution;

[0084] (2) The polyamide reverse osmosis membrane is contacted with the coating solution, and then heat-treated to obtain a composite reverse osmosis membrane.

[0085] In a preferred embodiment, the preparation method of the composite reverse osmosis membrane of the present invention comprises the following steps:

[0086] (1) Add polyvinyl alcohol or its aqueous solution to the tannic acid aqueous solution, stir evenly, and optionally adjust the pH to 3-6 to obtain polyvinyl alcohol with a mass fraction of 0.1-8%, polyvinyl alcohol and tannic acid The mass ratio is (5-500): 1 coating solution...

Embodiment 1

[0111] Add tannic acid to the water, stir evenly, then add polyvinyl alcohol aqueous solution, stir evenly, adjust the pH with dilute hydrochloric acid, and obtain a mass fraction of polyvinyl alcohol of 0.8%, and a mass ratio of polyvinyl alcohol to tannic acid of 30:1. A coating solution with a pH of 5.36; soak the surface of the aromatic polyamide reverse osmosis membrane after rinsing in the coating solution, contact it at 25°C for 10 seconds, air-dry it, transfer it to an oven for drying treatment, and dry it at 100°C for 1 minute to obtain The anti-pollution polyamide composite reverse osmosis membrane has a hydrophilic and smooth surface without adhesion.

[0112] The prepared composite reverse osmosis membrane has a surface chemical structure with a C / O ratio of 62.8 / 37.2 and an N / O ratio of 0 / 100. The initial performance was measured at 25°C, 2000ppm NaCl feed liquid, and 1.55MPa for 30 minutes, and the flux was 54.78L / (m 2 *h), the desalination rate is 99.71%; the r...

Embodiment 2

[0114] Add tannic acid to the water, stir evenly, then add polyvinyl alcohol aqueous solution, stir evenly, adjust the pH with dilute hydrochloric acid, and obtain a mass fraction of polyvinyl alcohol of 1.5%, and a mass ratio of polyvinyl alcohol to tannic acid of 15:1. A coating solution with a pH of 5.94; apply the coating solution on the surface of the rinsed aromatic polyamide reverse osmosis membrane, transfer it to an oven for drying treatment, and dry it at 120°C for 2 minutes to obtain an anti-pollution polyamide composite reverse osmosis membrane , the appearance showed a hydrophilic smooth surface, showing no adhesion.

[0115] The prepared composite reverse osmosis membrane has a surface chemical structure with a C / O ratio of 62.2 / 37.8 and an N / O ratio of 0 / 100. The initial performance was measured at 25°C, 2000ppm NaCl feed liquid, and 1.55MPa for 30 minutes, and the flux was 50.12L / (m 2 *h), the desalination rate is 99.63%; the replacement raw material solution ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
degree of polymerizationaaaaaaaaaa
salt rejection rateaaaaaaaaaa
recovery rateaaaaaaaaaa
Login to view more

Abstract

The invention provides an anti-pollution composite reverse osmosis membrane and a preparation method thereof. The composite reverse osmosis membrane comprises a polyamide reverse osmosis membrane and an antifouling layer located on the surface of the polyamide reverse osmosis membrane, and the antifouling layer comprises tannic acid and polyvinyl alcohol. The method comprises the step of making the polyamide reverse osmosis membrane contact with a coating solution, wherein the coating solution is an aqueous solution containing tannic acid and polyvinyl alcohol. The surface of the polyamide reverse osmosis membrane is coated with the coating solution through a one-step method, the process is simple, and the industrialization operability is high. The anti-pollution composite reverse osmosis membrane disclosed by the invention is high in flux, good in selectivity, strong in anti-pollution property and long in service life, has a hydrophilic smooth surface in appearance, and is beneficial to later-stage assembly rolling of the membrane.

Description

technical field [0001] The invention belongs to the field of reverse osmosis membranes, and relates to an anti-pollution composite reverse osmosis membrane and a preparation method thereof. Background technique [0002] Reverse osmosis membrane technology has been widely used in the fields of drinking water, seawater desalination, industrial water treatment, wastewater treatment and reuse, and has achieved significant social and economic benefits. Among them, the aromatic polyamide composite membrane prepared by interfacial polymerization is the most commonly used membrane material for reverse osmosis membrane technology. For the aromatic polyamide composite membrane, how to improve its long-term service life without compromising its production capacity and desalination rate is a key issue in controlling the operating cost of reverse osmosis. [0003] At present, the most commonly used method in the industry to prepare anti-fouling reverse osmosis membranes is generally to ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B01D69/12B01D69/02B01D67/00C02F1/44
CPCB01D69/12B01D69/125B01D67/0006B01D67/0002B01D69/02C02F1/441Y02A20/131
Inventor 殷勇钮振强郝长青崔健曹敏张韦海曹春朱建军
Owner 中化(宁波)润沃膜科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap