System and method for organic solvent purification

Patent metadata

Field	Value
Publication number	US-2017158635-A1
Application number	US-201515327504-A
Country	US
Kind code	A1
Filing date	Jul 22, 2015
Priority date	Jul 29, 2014
Publication date	Jun 8, 2017
Grant date	—

Abstract

An organic solvent purification system that separates an organic solvent having a boiling point of more than 100° C. at 1 atm, such as N-methyl-2-pyrrolidone (NMP), from a liquid mixture containing the organic solvent and water and purifies the organic solvent includes: a heater that heats the liquid mixture; a pervaporation apparatus that includes a pervaporation membrane, and is provided at subsequent position of the heater, the pervaporation apparatus separating the organic solvent from the water; a vacuum evaporator to which the organic solvent collected from a concentration side of the pervaporation apparatus is supplied; and piping that supplies the heater with the organic solvent vaporized in the vacuum evaporator as a heat source of the heater. The heater heats the liquid mixture using concentration heat of the organic solvent vaporized by the vacuum evaporator.

First claim

1 . An organic solvent purification system that separates an organic solvent having a boiling point of more than 100° C. at 1 atm from a liquid mixture containing water and the organic solvent, and purifies the organic solvent, the organic solvent purification system comprising:
a heater that heats the liquid mixture;
a pervaporation apparatus provided at subsequent position of said heater, the pervaporation apparatus including a pervaporation membrane and separating the organic solvent from the water;
a vacuum evaporator to which the organic solvent collected from a concentration side of said pervaporation apparatus is supplied; and
piping that supplies said heater with the organic solvent vaporized in said vacuum evaporator as a heat source of said heater.

2 . The organic solvent purification system according to claim 1 , further comprising an ion exchanger provided at preceding position of said heater, the ion exchanger carrying out ion exchange processing of the liquid mixture.

3 . The organic solvent purification system according to claim 1 , comprising a degassing apparatus provided at preceding position of said heater, the degassing apparatus removing gas components contained in the liquid mixture.

4 . The organic solvent purification system according to claim 1 , further comprising:
a degassing apparatus that is supplied with the liquid mixture, and removes gas components contained in the liquid mixture; and an ion exchanger that carries out ion exchange processing of the liquid mixture processed by said degassing apparatus, wherein the liquid mixture after being subjected to the ion exchange processing is supplied to said heater.

5 . The organic solvent purification system according to claim 3 , wherein said degassing apparatus includes a degassing membrane.

6 . The organic solvent purification system according to claim 3 , further comprising:
a tank that reserves the liquid mixture; and piping that circulates the liquid mixture between said degassing apparatus and said tank.

7 . The organic solvent purification system according to claim 1 , wherein
said pervaporation apparatus is configured by connecting in series a first pervaporation apparatus and a second pervaporation apparatus to which a liquid discharged from a concentration side of said first pervaporation apparatus is supplied, the organic solvent collected from a concentration side of said second pervaporation apparatus is supplied to said vacuum evaporator, and said organic solvent purification system further includes piping that circulates a liquid discharged from a permeation side of said second pervaporation apparatus to preceding position of said first pervaporation apparatus.

8 . The organic solvent purification system according to claim 1 , wherein the organic solvent comprises N-methyl-2-pyrrolidone.

9 . A method that separates an organic solvent having a boiling point of more than 100° C. at 1 atm from a liquid mixture containing water and the organic solvent, and purifies the organic solvent, the method comprising the steps of:
heating the liquid mixture;
separating the heated liquid mixture into the organic solvent and the water using a pervaporation membrane; and
carrying out vacuum evaporation of the organic solvent collected from a concentration side of said pervaporation membrane,
wherein the organic solvent vaporized through the vacuum evaporation is used as a heat source in said heating step.

10 . The organic solvent purification system according to claim 2 , comprising a degassing apparatus provided at preceding position of said heater, the degassing apparatus removing gas components contained in the liquid mixture.

11 . The organic solvent purification system according to claim 4 , wherein said degassing apparatus includes a degassing membrane.

12 . The organic solvent purification system according to claim 4 , further comprising:
a tank that reserves the liquid mixture; and piping that circulates the liquid mixture between said degassing apparatus and said tank.

13 . The organic solvent purification system according to claim 12 , wherein said degassing apparatus includes a degassing membrane.

14 . The organic solvent purification system according to claim 7 , further comprising:
a degassing apparatus that is supplied with the liquid mixture, and removes gas components contained in the liquid mixture; and an ion exchanger that carries out ion exchange processing of the liquid mixture processed by said degassing apparatus, wherein the liquid mixture after being subjected to the ion exchange processing is supplied to said heater.

15 . The organic solvent purification system according to claim 14 , wherein said degassing apparatus includes a degassing membrane.

16 . The organic solvent purification system according to claim 15 , further comprising:
a tank that reserves the liquid mixture; and piping that circulates the liquid mixture between said degassing apparatus and said tank.

17 . The organic solvent purification system according to claim 7 , wherein the organic solvent comprises N-methyl-2-pyrrolidone.

18 . The organic solvent purification system according to claim 14 , wherein the organic solvent comprises N-methyl-2-pyrrolidone.

Assignees

• Organo Corp

Inventors

• Terashi Ryosuke

Classifications

• C07D207/267 Primary

  with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to the ring nitrogen atom · CPC title

• B01D61/58 Primary

  Multistep processes · CPC title

• C02F1/448

  by pervaporation · CPC title

• C02F1/20

  by degassing, i.e. liberation of dissolved gases (degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D) · CPC title

• B01D2311/06

  Specific process operations in the permeate stream · CPC title