Unlock instant, AI-driven research and patent intelligence for your innovation.

Preparation method of forward osmosis membrane

A technology of forward osmosis membrane and scraping membrane, which is applied in the field of preparation of forward osmosis membrane, can solve the problems of reducing the driving force of the osmosis process, low pollution degree, and low energy consumption, and achieves increased salt rejection rate, good compatibility, and increased ratio The effect of surface area

Inactive Publication Date: 2016-11-30
ANHUI SONGTAI PACKAGING MATERIALS
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The forward osmosis process does not require external pressure, less energy consumption, less pollution to the membrane, higher process recovery rate, and friendly environmental effects. Due to these advantages of the forward osmosis process, it is used in seawater desalination and brackish water desalination. , Food concentration, power generation, drug controlled release and other fields have broad development space. The performance indicators for evaluating forward osmosis membrane materials include flux and the interception capacity of membrane materials for salt, referred to as salt rejection rate. In the process of forward osmosis, semi-permeable The osmotic pressure difference on both sides of the membrane can be much higher than the driving force in the reverse osmosis process. In theory, forward osmosis can achieve much higher permeation than reverse osmosis, but because of the existence of internal concentration polarization, the effective osmotic pressure Difference Δπ eff It is much smaller than the osmotic pressure difference Δπ between the drive liquid and the feed liquid, which greatly reduces the driving force of the osmotic process, so the actual flux is much smaller than the theoretical flux

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] Embodiment 1: a kind of preparation method of forward osmosis membrane, comprises the following steps:

[0019] 1) Preparation of casting solution: 38 wt% of cellulose acetate and 1 wt% of nano-materials are mixed in a solvent, stirred and dissolved at a temperature of 50° C. to form a uniform casting solution;

[0020] Among them, nano-materials include nano-TiO 2 , nano-SiO 2 and a mixture of zeolite molecular sieves loaded with metal ions, nano-TiO 2 , nano-SiO 2 The ratio to the zeolite molecular sieve loaded with metal ions is 1.5:1:2.5,

[0021] Wherein, the solvent is a mixture of N-N-dimethylformamide and methanol (1:1);

[0022] 2) Ultrasonic degassing: Ultrasonic degassing is performed on the casting solution prepared in step 1);

[0023] 3) Scraping film: apply the defoamed casting solution in step 2) on a dry and clean glass plate, and use a scraping machine to form an initial scraping film at a temperature of 40°C and a relative humidity of 65%. eco-f...

Embodiment 2

[0026] Embodiment 2: a kind of preparation method of forward osmosis membrane, comprises the following steps:

[0027] 1) Preparation of casting solution: 30 wt% of cellulose acetate and 1.5 wt% of nano-materials are mixed in a solvent, stirred and dissolved at a temperature of 45° C. to form a uniform casting solution;

[0028] Among them, nano-materials include nano-TiO 2 , nano-SiO 2 and a mixture of zeolite molecular sieves loaded with metal ions, nano-TiO 2 , nano-SiO 2 The ratio to the zeolite molecular sieve loaded with metal ions is 1.2:1:1.8,

[0029] Wherein, the solvent is a mixture of N-methylpyrrolidone and ethyl acetate (1:0.01);

[0030] 2) Ultrasonic degassing: Ultrasonic degassing is performed on the casting solution prepared in step 1);

[0031] 3) Scraping film: apply the defoamed casting solution in step 2) on a dry and clean glass plate, and pass through a film scraping machine to form an initial scraping film at a temperature of 30°C and a relative h...

Embodiment 3

[0034] Embodiment 3: a kind of preparation method of forward osmosis membrane, comprises the following steps:

[0035] 1) Preparation of casting solution: 25 wt% of cellulose acetate and 0.1 wt% of nano-materials are mixed in a solvent, stirred and dissolved at a temperature of 60° C. to form a uniform casting solution;

[0036] Among them, nano-materials include nano-TiO 2 , nano-SiO 2 and a mixture of zeolite molecular sieves loaded with metal ions, nano-TiO 2 , nano-SiO 2 The ratio to the zeolite molecular sieve loaded with metal ions is 1.3:1:2,

[0037] Wherein, the solvent is a mixture of propylene carbonate and tetrahydrofuran (1:0.1).

[0038] 2) Ultrasonic degassing: Ultrasonic degassing is performed on the casting solution prepared in step 1);

[0039]3) Scraping film: apply the defoaming-treated casting solution in step 2) on a dry and clean glass plate, and use a scraping machine to form an initial scraping film at a temperature of 35°C and a relative humidity...

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
pore sizeaaaaaaaaaa
Login to View More

Abstract

Relating to the field of high polymer films, the invention discloses a preparation method of a forward osmosis membrane. The method includes the steps of: 1) preparation of a casting solution; 2) ultrasonic deaeration; 3) membrane scraping; 4) gelling bath; and 5) rinsing. The method provided by the invention on the one hand overcomes the defect of low flux in existing forward osmosis membranes by selecting appropriate preparation steps and preparation materials, and also improves the membrane permeation flux and antipollution and antibacterial ability by adding nano-materials.

Description

technical field [0001] The invention relates to the field of polymer membranes, in particular to a method for preparing a forward osmosis membrane. Background technique [0002] Most of the earth's surface is covered by oceans, and only 0.8% of the water resources are drinkable fresh water. With the increasing environmental pollution, the world is facing serious water resources, environment and energy crises. Exploitation and utilization of seawater, which accounts for more than 99% of the earth's surface, is an effective way to solve the water resource crisis. However, the reverse osmosis technology widely used in seawater desalination needs to apply a large external pressure and consumes a lot of energy. Forward osmosis technology is a new water treatment technology born to solve this key problem. Forward osmosis technology is to place solutions with different osmotic pressures on both sides of the semi-permeable membrane, and water will spontaneously flow from the low o...

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): B01D71/16B01D71/02B01D69/02B01D67/00
CPCB01D71/16B01D67/0079B01D69/02B01D71/024B01D71/027B01D71/028B01D2325/48
Inventor 焦国平齐继业方兴旺
Owner ANHUI SONGTAI PACKAGING MATERIALS