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

Method for recovering N-methylmorpholine-N-oxide and system

A technology of methylmorpholine and recovery methods, applied in chemical instruments and methods, organic chemistry, water/sludge/sewage treatment, etc., can solve problems such as high COD equivalent wastewater and environmental secondary pollution, and achieve secondary pollution less, less corrosive equipment, and efficient recovery

Pending Publication Date: 2021-06-11
HEBEI HUAMAO WEIYE TECH CO LTD +1
View PDF8 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The main purpose of the present invention is to provide a kind of recovery method and recovery system of N-methylmorpholine-N-oxide compound, to overcome the N-methylmorpholine-N in the lyocell fiber coagulation bath discharge liquid in the prior art - The oxide recovery process produces a large amount of waste water with high COD equivalent and high salt content, causing secondary pollution to the environment

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
  • Method for recovering N-methylmorpholine-N-oxide and system
  • Method for recovering N-methylmorpholine-N-oxide and system
  • Method for recovering N-methylmorpholine-N-oxide and system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0098] Step 1, mixing the discharge liquid of the lyocell fiber coagulation bath with the acrylamide coagulant aid for flocculation and sedimentation;

[0099] In step 2, the mixed liquid obtained in step 1 is subjected to microporous filtration, the microporous filtration precision is 0.5-5 microns, to intercept the solid matter, and obtain the microporous filtrate, the NMMO content in the microporous filtrate is 150-250 g / L;

[0100] Step 3, the microporous filtrate is subjected to primary nanofiltration treatment, the molecular weight cut-off is 800-2000 Daltons, N-methylmorpholine-N-oxide enters the primary nanofiltration filtrate, pigments, polysaccharides Molecular impurities such as substances, metal complexes, and high-valent ions are intercepted to obtain a first-level nanofiltration concentrate with a concentration factor of 20 times. The NMMO content in the first-level nanofiltration concentrate is 150-250 g / L; then add Water with 3 times the volume of the primary n...

Embodiment 2

[0102] Step 1, mixing the discharge liquid of the lyocell fiber coagulation bath with the acrylamide coagulant aid for flocculation and sedimentation;

[0103] In step 2, the mixed liquid obtained in step 1 is subjected to microporous filtration, the microporous filtration precision is 0.5-5 microns, to intercept the solid matter, and obtain the microporous filtrate, the NMMO content in the microporous filtrate is 150-250 g / L; The liquid chromatogram of gained microporous filtrate is as follows Figure 5 Shown, wherein peak 1 is the characteristic peak of NMMO, and the rest are impurity peaks.

[0104] Step 3, subjecting the microporous filtrate to ultrafiltration, with a molecular weight cut-off of 10,000-30,000 Daltons, to intercept small particle size solids, colloids, and macromolecular impurities, and the obtained ultrafiltration concentrate is 5% of the volume of the microporous filtrate , the NMMO content in both the ultrafiltration concentrate and the ultrafiltration ...

Embodiment 3

[0114] Step 1, mixing the discharge liquid of the lyocell fiber coagulation bath with the acrylamide coagulant aid for flocculation and sedimentation;

[0115] In step 2, the mixed solution obtained in step 1 is subjected to microporous filtration, and the microporous filtration accuracy is 0.5 to 5 microns to intercept solids to obtain a microporous filtrate, and the content of NMMO in the microporous filtrate is 150-250 g / Lift.

[0116] Step 3, the microporous filtrate is subjected to primary nanofiltration treatment, the molecular weight cut-off is 800-2000 Daltons, N-methylmorpholine-N-oxide and monovalent salt enter the primary nanofiltration filtrate, Medium-molecular impurities such as pigments, polysaccharides, metal complexes, and high-valent ions are intercepted, and a first-level nanofiltration concentrate with a concentration factor of 10 times is obtained. The NMMO content in the first-level nanofiltration concentrate is 150-250 g / Then add water 10 times the vo...

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

No PUM Login to View More

Abstract

The invention discloses a method for recovering N-methylmorpholine-N-oxide and a system thereof, the N-methylmorpholine-N-oxide comes from a discharged liquid of a lyocell fiber coagulating bath, the method comprises the following steps: step 1, mixing the discharged liquid of the lyocell fiber coagulating bath with a coagulant aid to obtain a mixed liquid, and carrying out flocculating settling; step 2, carrying out microporous filtration treatment on the mixed solution to obtain a microporous filtrate; and step 3, performing primary nanofiltration treatment on the microporous filtrate to obtain a primary nanofiltration concentrated solution and a primary nanofiltration filtrate. According to the method, the lyocell fiber coagulating bath discharge liquid is treated by adopting a membrane technology, so that high-COD impurities and high-salt impurities are removed step by step, the problem that wastewater which is difficult to treat is generated in a lyocell fiber coagulating bath discharge liquid treatment process in the prior art is avoided, and high-purity N-methylmorpholine-N-oxide can be efficiently recycled.

Description

technical field [0001] The invention relates to the field of lyocell fiber production, in particular to a recovery method and a recovery system for NMMO in a coagulation bath discharge liquid of a lyocell fiber production process. Background technique [0002] In the production process of lyocell fiber, the lyocell fiber pulp is firstly dissolved in high-concentration NMMO (N-methylmorpholine-N-oxide) ionic liquid, and the resulting mixture is spun into pure water, lyocell The lyocell fiber is separated out, and then the lyocell fiber product is produced through subsequent refining, drying and other treatment processes; the liquid obtained after the lyocell fiber is separated out is called the discharge liquid of the lyocell fiber coagulation bath, due to the dilution of pure water, the discharged The concentration of NMMO in the solution is low. In the prior art, the process of recovering NMMO from the effluent of the lyocell fiber coagulation bath is mainly as follows: ad...

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): C02F9/04C07D295/03C07D295/023
CPCC02F9/00C07D295/03C07D295/023C02F1/56C02F1/001C02F1/442C02F1/441C02F1/444
Inventor 马杰路万里张峰敏付涛徐天祥王沛
Owner HEBEI HUAMAO WEIYE TECH CO LTD