Preparation method of layer-by-layer self-assembling forward osmosis membrane and layer-by-layer self-assembling forward osmosis membrane prepared by method

A layer-by-layer self-assembly, forward osmosis membrane technology, applied in the field of membrane separation, can solve the problems of high salt reverse osmosis, poor membrane stability, low membrane water flux, etc., to achieve good separation performance, short preparation time, preparation simple craftsmanship

Inactive Publication Date: 2015-04-22
OCEAN UNIV OF CHINA
View PDF3 Cites 30 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to solve the technical problems in the prior art that the preparation of layer-by-layer self-assembled forward osmosis membranes takes more time, the stability of the membrane is poor, the water flux of the membrane is low, and the amount of salt reverse osmosis is high, and to provide a A method for preparing a layer-by-layer self-assembled forward osmosis membrane. The preparation method uses metal ion coordination to improve the deposition effect, simplify the process steps, and shorten the preparation time. The layer-by-layer self-assembled forward osmosis membrane ensures good separation performance of the membrane , the prepared membrane has high water flux and low salt reverse osmosis

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
  • Preparation method of layer-by-layer self-assembling forward osmosis membrane and layer-by-layer self-assembling forward osmosis membrane prepared by method
  • Preparation method of layer-by-layer self-assembling forward osmosis membrane and layer-by-layer self-assembling forward osmosis membrane prepared by method
  • Preparation method of layer-by-layer self-assembling forward osmosis membrane and layer-by-layer self-assembling forward osmosis membrane prepared by method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] The base membrane is a polyacrylonitrile (PAN) flat ultrafiltration membrane with a molecular weight cut-off of 50,000Da (Dalton); polyethyleneimine (PEI) with an average molecular weight of 60,000Da is used as a cationic polyelectrolyte; sodium polystyrene sulfonate with an average molecular weight of 70,000Da (PSS) as the anionic polyelectrolyte; sodium chloride as the first and second supporting electrolyte; copper chloride dihydrate as the complexing agent.

[0036] Step 1: Modification of base film

[0037] The base film was immersed in 2mol / L NaOH solution, soaked at 65°C for 1 hour to obtain a modified base film with a charged surface. After modification, the base film was rinsed with deionized water and stored in deionized water;

[0038] Step 2: Preparation of cationic polyelectrolyte solution

[0039] Dissolve the cationic polyelectrolyte in deionized water, and add the first supporting electrolyte to prepare a cationic polyelectrolyte solution with a mass co...

Embodiment 2

[0048] The modification process of the base membrane is the same; the mass concentration of the cationic polyelectrolyte polyethyleneimine (PEI) is 1 g / L, the molar concentration of the first supporting electrolyte sodium chloride is 0.5 mol / L, and the pH value is 11; the anionic polyelectrolyte polystyrene sulfonate The mass concentration of sodium bicarbonate (PSS) is 1g / L, the second supporting electrolyte sodium chloride is 0.5mol / L, and the complexing agent copper chloride is 0.3mol / L; Rinse with ionized water to form a forward osmosis membrane with three polyelectrolyte double layers. After the same conditions and equipment evaluation, the water flux of the prepared layer-by-layer self-assembled forward osmosis membrane was 13.02LMH, and the reverse salt flux was 3.07gMH.

Embodiment 3

[0050] The modification process of the base membrane is the same; the mass concentration of the cationic polyelectrolyte polyethyleneimine (PEI) is 1 g / L, the molar concentration of the first supporting electrolyte sodium oxide is 0.5 mol / L, and the pH value is 11; the anionic polyelectrolyte polystyrene sulfonic acid The mass concentration of sodium (PSS) is 1g / L, the second supporting electrolyte sodium oxide is 0.5mol / L, and the complexing agent copper chloride is 0.2mol / L; the single-layer deposition time is 10min, and deionized water is used for 2min between each soaking interval Rinse to form a forward osmosis membrane with 4 polyelectrolyte double layers. After the same conditions and equipment evaluation, the water flux of the prepared layer-by-layer self-assembled forward osmosis membrane was 11.54LMH, and the reverse salt flux was 1.34gMH.

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
molecular weightaaaaaaaaaa
molecular weightaaaaaaaaaa
concentrationaaaaaaaaaa
Login to view more

Abstract

The invention relates to a preparation method of a layer-by-layer self-assembly forward osmosis membrane and a layer-by-layer self-assembling forward osmosis membrane prepared by the method. The preparation method comprises the steps of carrying out modified treatment on a basic membrane, preparing a cationic polyelectrolyte solution, preparing an anionic polyelectrolyte and preparing a multilayer self-assembling membrane. By adopting the method, the deposition process in the prior art for adsorption only by virtue of an electrostatic effect can be changed, and a coordination effect better than the electrostatic effect is used as the driving force of the deposition process, so that the membrane has the characteristics of high water flux and low salt reverse osmotic quantity, other subsequent processes such as GA cross-linking and UV radiation are not needed, and thus the time for the preparation process can be greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of membrane separation, and in particular relates to a method for preparing a layer-by-layer self-assembled forward osmosis membrane and a layer-by-layer self-assembled forward osmosis membrane prepared by the method. Background technique [0002] The world is currently facing a water shortage that cannot be ignored. On the one hand, the proportion of available fresh water resources is small; on the other hand, the development of the three major industries and the unstoppable increase of the world population have caused serious water pollution. The above two factors have further reduced the proportion of available fresh water resources. Clean fresh water has become a key factor restricting the sustainable development of human beings. Energy conservation and emission reduction, development of new water resources and reduction of water pollution have become an urgent problem to be solved. [0003] Compared w...

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): B01D67/00B01D71/42B01D61/00
Inventor 苏保卫魏桐李峰黄良伟
Owner OCEAN UNIV OF CHINA
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