Treatment method for zero discharge of ionic liquid water solution

A technology of ionic liquid and treatment method, which is applied in the field of zero-discharge treatment of ionic liquid aqueous solution, can solve problems such as complicated process and difficult practical application, and achieve the effect of reliable process, high product quality and easy realization

Active Publication Date: 2008-07-23
INST OF CHEM CHINESE ACAD OF SCI +1
View PDF2 Cites 37 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although these two methods have good enrichment effects, the process is relatively complicated and needs further research, and it is still difficult to be practically applied at present.

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
  • Treatment method for zero discharge of ionic liquid water solution

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Embodiment 1, zero discharge treatment of ionic liquid aqueous solution

[0036] The dilute aqueous solution of 1-allyl-3-methylimidazolium chloride salt was treated with the JM 1812 roll-type membrane small-scale experimental machine. The reverse osmosis membrane used was polyamide reverse osmosis membrane, and the manufacturer was Dalian Yidong Membrane Engineering Equipment. Ltd. The concentration of the raw material solution was changed, and the concentration treatment of the reverse osmosis membrane was carried out in a circulation mode under a specified working pressure, and the content of the ionic liquid in the aqueous solution was measured with a conductivity and an ultraviolet spectrophotometer. The results are shown in Table 1.

[0037] Table 1 Concentration of ionic liquid 1-allyl-3-methylimidazolium dilute aqueous solution by reverse osmosis

[0038] Raw material concentration

work pressure

Concentrate concentration

Permeate concentrat...

Embodiment 2

[0041] Embodiment 2, zero discharge treatment of ionic liquid aqueous solution

[0042] When the ionic liquid 1-allyl-3-methylimidazolium chloride salt is used as a solvent for small-scale production of cellulose spinning, the treatment process for the generated low-concentration ionic liquid aqueous solution includes the following four steps in sequence: pretreatment, two Stage circulation reverse osmosis membrane concentration treatment, one effect decompression evaporation treatment, one effect scraping film evaporation treatment.

[0043] First, the above-mentioned ionic liquid aqueous solution is divided into two levels for collection: the first level is a very dilute solution with a salt content of not more than 0.05-0.25%; the other level is a dilute solution with a concentration of not more than 5%. The above two solutions were subjected to coarse filtration and 0.5 micron fine filtration respectively.

[0044] After that, reverse osmosis membrane concentration treatm...

Embodiment 3

[0047] Embodiment 3, zero discharge treatment of ionic liquid aqueous solution

[0048] When using ionic liquid 1-allyl-3-methylimidazolium chloride salt as solvent to produce cellulose acetate, the product is washed with water for many times, and the obtained ionic liquid aqueous solutions with different concentrations are collected according to the following three levels: 1-5%, 0.1 -0.5%, 0.01-0.05%. In order to ensure the normal operation of the reverse osmosis device, the recovered solution is first adjusted to pH (adjusted to pH 6.5-7), decolorized, rough filtered, 0.5 micron fine filtered and 6K ultrafiltered.

[0049] Then use high-pressure, medium-pressure, and low-pressure three-stage reverse osmosis membrane concentration devices to process the above three ionic liquid aqueous solutions respectively. The reverse osmosis membrane used is a roll-type polyamide composite membrane, the membrane element is 8040 type, and the manufacturer is Dalian Yidong Membrane Enginee...

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
recovery rateaaaaaaaaaa
salt rejection rateaaaaaaaaaa
recovery rateaaaaaaaaaa
Login to view more

Abstract

The invention discloses a processing method of zero drainage of ion liquid aqueous solution, which comprises the following steps in sequence: 1) a membrane concentrating set is used for concentrating the ion liquid aqueous solution to 5-15 percent; a membrane element is the combination of a reverse osmosis membrane or a nanofiltration membrane and a reverse osmosis membrane element; 2) one or any combination of flash evaporation, falling film evaporation or climbing film evaporation is used for concentrating the solution to 60-90 percent; 3) a movable scraper type wiped film evaporator is used for concentrating the solution to more than 95 percent. The method combines the advantages of membrane concentration, reduction vaporization and wiped film evaporation technology, thus completely recycling ion liquid and water of 0.005-10 percent of ion liquid aqueous solution; the pureness of the ion liquid obtained is more than 95 percent and the salt content of the water is lower than 0.001 percent. The method is characterized by saving energy and water, reliable technique, high product quality, easy realization and wide adaption scope, thus having important practical value in the green chemical field that uses the ion liquid as a solvent.

Description

technical field [0001] The invention relates to a zero-discharge treatment method for an ionic liquid aqueous solution, in particular to a method for recovering an ionic liquid from a low-concentration ionic liquid aqueous solution. Background technique [0002] Ionic liquids, also known as room temperature ionic liquids, refer to organic salts whose melting point is close to room temperature (or lower than 100°C). As a salt that melts at room temperature, ionic liquids have attracted widespread attention due to their unique excellent solvent properties, strong polarity, and low volatility. attention of the world. In the field of cellulose chemistry, the new technology of using ionic liquids to prepare regenerated cellulose products and cellulose derivatives has many advantages, and has attracted wide interest in the academic circle and close attention in the industry. Since cellulose has many hydroxyl groups, the ionic liquids that can be used to dissolve and process cell...

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): C02F9/10C02F1/44C02F1/04
CPCY02P20/10
Inventor 武进王三元张军王东兴何嘉松魏广信
Owner INST OF CHEM CHINESE ACAD OF SCI
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