Method of preparing aromatic vinyl compound-vinyl cyanide compound polymer and apparatus for preparing the same

Patent metadata

Field	Value
Publication number	US-11512153-B2
Application number	US-201916634094-A
Country	US
Kind code	B2
Filing date	Aug 1, 2019
Priority date	Dec 18, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

The present invention relates to a method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer including a step of separating volatile components from a polymerization product containing an aromatic vinyl compound-vinyl cyanide compound polymer, a residual aromatic vinyl monomer, a residual vinyl cyanide monomer, and an organic solvent using a volatilization tank, and a step of condensing the separated volatile components using a condenser, wherein an organic solvent or an aromatic vinyl monomer is sprayed onto the volatile components being transferred to the condenser. Volatile components may be fully condensed in a condenser, thereby significantly reducing the amount of volatile components discharged to the outside without being condensed. Therefore, wastewater treatment costs consumed in treating the volatile components may be reduced, and the amount of vinyl cyanide monomers harmful to the human body discharged into the atmosphere may be significantly reduced.

First claim

The invention claimed is:

1. A method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer, comprising:
separating volatile components from a polymerization product containing an aromatic vinyl compound-vinyl cyanide compound polymer, residual aromatic vinyl monomer, residual vinyl cyanide monomer, and an organic solvent using a volatilization tank; and
condensing the separated volatile components using one condenser or two or more condensers connected in series,
wherein the method comprises spraying an organic solvent onto the separated volatile components being transferred from the volatilization tank to the condenser; or
spraying an organic solvent or an aromatic vinyl monomer onto the volatile components not being condensed in a first condenser and being transferred to a second condenser when the two or more condensers connected in series are used.

2. The method according to claim 1 , wherein the method comprises spraying the organic solvent onto the volatile components being transferred to the first condenser after being separated in the volatilization tank; and
spraying the organic solvent or the aromatic vinyl monomer onto the volatile components not being condensed in the first condenser and being transferred to the second condenser.

3. The method according to claim 1 , wherein the separated volatile components comprise 5 to 35% by weight of a vinyl cyanide compound, 45 to 80% by weight of an aromatic vinyl compound, and 5 to 50% by weight of an organic solvent.

4. The method according to claim 1 , wherein, in the spraying of the organic solvent, the organic solvent is sprayed at a flow rate of 10 to 200 kg/hr.

5. The method according to claim 1 , wherein, in the spraying of the organic solvent, the organic solvent is sprayed at a temperature of −10 to 40° C.

6. The method according to claim 1 , wherein, in the spraying of the organic solvent or the aromatic vinyl monomer, the organic solvent or the aromatic vinyl monomer is sprayed at a flow rate of 10 to 220 kg/hr.

7. The method according to claim 1 , wherein, in the spraying of the organic solvent or the aromatic vinyl monomer onto the volatile components not being condensed in the first condenser and being transferred to the second condenser, the organic solvent or the aromatic vinyl monomer is sprayed at a temperature of −10 to 40° C.

8. The method according to claim 1 , wherein condensation in the first condenser is performed at a refrigerant temperature of 20 to 35° C. under an operating pressure of 3 to 100 Torr.

9. The method according to claim 1 , wherein condensation in the second condenser is performed at a refrigerant temperature of −3 to 4° C. under an operating pressure of 5 to 50 Torr.

10. The method according to claim 1 , wherein the separating is performed at a temperature of 220 to 260° C. under a pressure of 35 Torr or less.

11. The method according to claim 1 , wherein condensates condensed in the first and second condensers are recovered, purified, and reintroduced into a reactor.

12. An apparatus for preparing an aromatic vinyl compound-vinyl cyanide compound polymer, comprising:
a volatilization tank for separating volatile components from a polymerization product containing an aromatic vinyl compound-vinyl cyanide compound polymer, residual aromatic vinyl monomer, residual vinyl cyanide monomer, and an organic solvent; and
one condenser or two or more condensers connected in series for condensing the separated volatile components,
wherein the apparatus comprises a spray means for spraying an organic solvent into a transfer pipe for transferring the separated volatile components to the condenser; or
a spray means for spraying an organic solvent or an aromatic vinyl monomer into a transfer pipe for transferring the volatile components, which have not been condensed in a first condenser, to a second condenser, when the two or more condensers connected in series are comprised.

13. The apparatus according to claim 12 , wherein the apparatus comprises a spray pipe for spraying the organic solvent into the transfer pipe for transferring the separated volatile components to the first condenser; and
a spray pipe for spraying the organic solvent or the aromatic vinyl monomer into the transfer pipe for transferring the volatile components, which have not been condensed in the first condenser, to the second condenser.

Assignees

• Lg Chemical Ltd

Inventors

• Hwang Jeong A
• Shin Daeyoung
• Jang Sungkeun
• Joo Eun Jung
• Lee Won Kyun

Classifications

• C08F6/001 Primary

  Removal of residual monomers by physical means · CPC title

• B01D3/10 Primary

  Vacuum distillation (B01D3/12 takes precedence) · CPC title

• C08F212/10

  with nitriles · CPC title

• C08F6/20

  Concentration · CPC title

• C08F2/01

  characterised by special features of the polymerisation apparatus used · CPC title