Reduced fouling process for the production of methyl methacrylate

Patent metadata

Field	Value
Publication number	US-2017334827-A1
Application number	US-201515521440-A
Country	US
Kind code	A1
Filing date	Oct 13, 2015
Priority date	Oct 27, 2014
Publication date	Nov 23, 2017
Grant date	—

Abstract

Fouling of an MMA process is reduced by acidifying a stream comprising recycled components.

First claim

What is claimed is:

1 . A process comprising: (a) contacting methacrylamide with methanol in an aqueous reaction medium in an esterification reaction zone in the presence of an acidic raw material to produce a first stream comprising MMA, water, methanol, the acidic raw material and MAA; (b) phase separating the first stream into a first aqueous stream comprising the acidic raw material, and a first organic liquid product stream comprising MMA, methanol and MAA; (c) neutralizing the MAA of the first organic liquid product stream with ammonia to produce a neutralized stream comprising MMA, methanol and ammonium methacrylate; (d) optionally adding water to the neutralized stream; (e) separating the neutralized stream into a second organic stream comprising MMA, and a second aqueous stream comprising methanol and ammonium methacrylate; (f) contacting the second aqueous stream with an acidifying agent to form an acidified aqueous stream; and (g) sending at least a portion of the acidified aqueous stream to the reaction zone.

2 . The process of claim 1 wherein the acidic raw material comprises at least one of sulfuric acid and oleum.

3 . The process of claim 1 wherein the acidifying agent comprises at least one of sulfuric acid and oleum.

4 . The process of claim 1 wherein the separating of step (e) comprises at least one of distillation and phase separation.

5 . The process of claim 1 wherein the separating of step (e) comprises phase separation.

6 . The process of claim 1 wherein the acidifying agent comprises fresh acid or acid taken from another process stream.

7 . The process of claim 6 wherein the acidifying agent comprises acid from another process stream.

8 . The process of claim 6 wherein the acidifying agent comprises fresh acid.

9 . The process of claim 1 wherein the amount of acidifying agent admixed with the second aqueous stream is an amount sufficient to acidify the second aqueous stream to a pH of less than 3 before it reaches the reaction zone.

10 . The process of claim 1 wherein the amount of acidifying agent admixed with the second aqueous stream is an amount sufficient to acidify the second aqueous stream to a pH of less than 1.75 before it reaches the reaction zone.

11 . The process of claim 1 wherein the contacting the second aqueous stream with an acidifying agent to form an acidified aqueous stream comprises admixing the acidifying agent with the second aqueous stream via a static mixer.

12 . The process of claim 5 wherein the phase separation is conducted in a decanter, the acidic raw material comprises sulfuric acid, the acidifying agent comprises sulfuric acid, and the amount of acidifying agent is an amount sufficient to acidify the second aqueous stream to a pH of less than 1.75 before it reaches the reaction zone.

13 . The process of claim 12 wherein the amount of acidifying agent is an amount sufficient to acidify the second aqueous stream to a pH of less than or equal to 1.5 before it reaches the reaction zone.

Assignees

• Rohm & Haas

Inventors

• Mendoza Joy L
• Maillot Philippe P
• Ye Mingyu
• Hoy Iv Stacy W

Classifications

• C07C69/54

  Acrylic acid esters; Methacrylic acid esters · CPC title

• C07C67/48 Primary

  Separation; Purification; Stabilisation; Use of additives · CPC title

• C07C67/54

  by distillation · CPC title

• C07C67/58

  by liquid-liquid treatment · CPC title

• C07C67/20 Primary

  from amides or lactams · CPC title