Graphene oxide modified PA (polyamide) composite nanofiltration membrane and preparation method thereof

A composite nanofiltration membrane and graphene modification technology, which is applied in the direction of chemical instruments and methods, membranes, membrane technology, etc. Poor water resistance, weak anti-pollution ability of nanofiltration membrane and other problems, to achieve the effect of easy operation, enhanced interlayer bonding tightness, and strong controllability

Active Publication Date: 2018-12-28
NANJING POLYTECHNIC INSITUTE
View PDF11 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the ultra-thin polyamide layer and the surface charge of the graphene oxide sheet endow the composite membrane with a high salt rejection rate, and the ultra-thin layer is thinner than the functional layer of the traditional polyamide nanofiltration membrane, which effectively reduces the membrane resistance and improves the water flux, but due to The ultra-thin amide layer and the graphene oxide sheet are not tightly combined and the mechanical strength is low, and the anti-fouling ability of the nanofiltration membrane is weak due to the poor hydrophilicity of the surface of the composite nanofiltration membrane

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
  • Graphene oxide modified PA (polyamide) composite nanofiltration membrane and preparation method thereof
  • Graphene oxide modified PA (polyamide) composite nanofiltration membrane and preparation method thereof
  • Graphene oxide modified PA (polyamide) composite nanofiltration membrane and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0033] A kind of preparation method of graphene oxide modified polyamide composite nanofiltration membrane, described method specifically comprises the steps:

[0034] Step 1: Prepare polyamide ultrafiltration base membrane: dissolve polyamide in N,N-dimethylformamide to prepare a casting solution containing polyamide with a mass concentration of 20-25%, at 65°C-70°C Stir, let stand at a constant temperature for degassing, cool to room temperature, pour the casting solution on a glass plate to scrape the film, put it in a water bath at 25°C to 28°C to solidify to form a film, soak it in deionized water to obtain a polyamide ultrafiltration base membrane ;

[0035]Step 2: Prepare an aqueous solution of aminated graphene oxide: add an alkaline solution to the graphene oxide solution, disperse evenly, and adjust the pH value of the solution to neutrality with hydrochloric acid, then centrifugally wash with deionized water, dissolve the product in deionized water and Add 1-(3-dim...

specific Embodiment

[0045] Specific examples are as follows:

[0046] A kind of preparation method of graphene oxide modified polyamide composite nanofiltration membrane, described preparation method specifically comprises the following steps:

[0047] (1) Preparation of polyamide ultrafiltration base membrane: dissolving polyamide in N,N-dimethylformamide to prepare a casting solution containing polyamide mass concentration of 20-25% (22, 23, 24), Stir at 65°C-70°C for 2.5-3.5 hours, and let it stand at constant temperature for 3-4 hours to degas. The membrane was removed from the glass plate and soaked in deionized water for 20-22 hours to obtain the polyamide ultrafiltration base membrane;

[0048] (2) Preparation of an aminated graphene oxide aqueous solution: add an alkaline solution to the graphene oxide solution, disperse evenly through ultrasound, and adjust the pH value of the solution to neutral with hydrochloric acid, then centrifugally wash with deionized water, and wash the product ...

Embodiment 4～6

[0058] Table 2 embodiment 4~6 concrete implementation scheme

[0059]

[0060] In conjunction with Table 2, it is known that when the final pH value of the aminated graphene oxide crosslinking solution is 12.5, the flux and desalination effect of the composite nanofiltration membrane are the best, wherein the rejection rate of sodium sulfate is 92.6%, and the rejection rate of magnesium sulfate is 92.6%. The rejection rate is 88.3%, the rejection rate of sodium chloride is 44.3%, the rejection rate of magnesium chloride is 77.2%, and the pure water flux is 35.6L m -2 h -1 .

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
thicknessaaaaaaaaaa
salt rejection rateaaaaaaaaaa
Login to view more

Abstract

The invention discloses a graphene oxide modified PA (polyamide) composite nanofiltration membrane and a preparation method thereof. The method comprises steps as follows: preparing a PA ultrafiltration basement membrane; preparing an aqueous amino graphene oxide solution; adding a crosslinking agent to the prepared aqueous amino graphene oxide solution to prepare an amino graphene oxide crosslinking solution; dip-coating the PA ultrafiltration basement membrane with a layer of the amino graphene oxide crosslinking solution with a surface coating method firstly, then coating the PA ultrafiltration basement membrane with a layer of a PA ultrafiltration membrane casting solution to prepare the graphene oxide modified PA composite nanofiltration membrane. A large quantity of free carboxyl andhydroxyl exist on the membrane surface, so that the graphene oxide modified PA composite nanofiltration membrane has the characteristics of high hydrophilcity and high throughput; meanwhile, due to the crosslinking reaction between amino graphene oxide and a PA basement membrane, tightness can be improved; the membrane surface is negatively charged, so that desalinization rate can be effectivelyincreased, and throughput and desalinization effect of the nanofiltration membrane are improved; the technical scheme has large-scale industrial application and popularization prospect.

Description

technical field [0001] The invention relates to the technical field of separation membrane preparation, in particular to a graphene oxide modified polyamide composite nanofiltration membrane and a preparation method thereof. Background technique [0002] Due to its unique structure and performance, separation membranes have emerged in environmental protection and water resource regeneration, especially in wastewater treatment and reclaimed water reuse. According to the different membrane pore sizes (or molecular weight cut-offs), membranes can be divided into microfiltration membranes, ultrafiltration membranes, nanofiltration membranes, and reverse osmosis membranes. [0003] Nanofiltration is between reverse osmosis and ultrafiltration, and the pore size is in the nanometer range, generally 0.5 to 2.0 nanometers. Compared with reverse osmosis membranes and ultrafiltration membranes, nanofiltration membranes have special properties and advantages, and have shown broad appl...

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): B01D71/56B01D61/00B01D69/12B01D67/00
CPCB01D61/027B01D67/0079B01D69/12B01D71/56B01D2325/24B01D2325/36
Inventor 杨福兴杨小燕伍凯飞蔡源关琦曲广淼
Owner NANJING POLYTECHNIC INSITUTE
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