Reducing polymer fouling and agglomeration in acrylate/methacrylate processes

Patent metadata

Field	Value
Publication number	US-2016102189-A1
Application number	US-201514881880-A
Country	US
Kind code	A1
Filing date	Oct 13, 2015
Priority date	Oct 14, 2014
Publication date	Apr 14, 2016
Grant date	—

Abstract

The present invention generally relates to a method for reducing polymer agglomeration or fouling, and its use in processes for the preparation of an acrylate, methacrylic acid, or a methacrylate. According to the present invention, the reagent comprises an alkyl phthalate, an alkaryl phthalate, an aryl phthalate, or a phthalic acid, and applying the reagent to processes for the preparation of an acrylate, methacrylic acid, or a methacrylate to prevent polymeric foulant precursors from agglomerating or to dissolve existing polymeric agglomerates or foulants so as to reduce polymer agglomeration or fouling in the process or storage equipment.

First claim

What is claimed is:

1 . A method of dispersing or dissolving a hydrocarbon foulant in a process fluid in contact with processing equipment for the preparation of an acrylate, methacrylic acid, or a methacrylate monomer comprising contacting the foulant with an effective amount of an organic solvent, the organic solvent comprising an alkyl phthalate, an alkaryl phthalate, an aryl phthalate, a phthalic acid, or a combination thereof.

2 . The method of claim 1 wherein the processing equipment is for preparation of methacrylic acid or methyl methacrylate.

3 . The method of claim 2 wherein the processing equipment for preparation of methacrylic acid or methyl methacrylate is adapted to the acetone cyanohydrin process.

4 . The method of claim 1 wherein the process fluid comprises sulfuric acid, an ammonium salt of sulfuric acid, or a combination thereof.

5 . The method of claim 4 wherein the process fluid comprises an acrylate, methacrylic acid, a methacrylate, or a combination thereof.

6 . The method of claim 5 wherein the process fluid comprises methacrylic acid, methyl methacrylate, or a combination thereof.

7 . The method of claim 1 wherein the hydrocarbon foulant comprises an oligomer or a polymer of acrylic acid, methacrylic acid, an acrylate, a methacrylate, a methacrylamide, or a combination thereof.

8 . The method of claim 7 wherein the hydrocarbon foulant comprises an oligomer or a polymer of methacrylic acid, methyl methacrylate, methacrylamide, or a combination thereof.

9 . The method of claim 1 wherein the organic solvent comprises a structure of Formula 1

wherein R 1 and R 2 are independently hydrogen, alkyl, alkaryl, or aryl.

10 . The method of claim 9 wherein R 1 and R 2 are independently hydrogen and C 1 -C 12 alkyl.

11 . The method of claim 9 wherein the organic solvent comprises phthalic acid, monomethyl phthalate, monoethyl phthalate, monononyl phthalate, monododecyl phthalate, monoundecyl phthalate, dimethyl phthalate, diethyl phthalate, dinonyl phthalate, didodecyl phthalate, diundecyl phthalate, monophenyl phthalate, monobenzyl phthalate, diphenyl phthalate, dibenzyl phthalate, or a combination thereof.

12 . The method of claim 11 wherein the organic solvent comprises dimethyl phthalate, diethyl phthalate, dinonyl phthalate, didodecyl phthalate, diundecyl phthalate, or a combination thereof.

13 . The method of claim 11 wherein the organic solvent comprises dinonyl phthalate, didodecyl phthalate, diundecyl phthalate, or a combination thereof.

14 . The method of claim 11 wherein the organic solvent is dimethyl phthalate, diethyl phthalate, or a combination thereof.

15 . The method of claim 11 wherein the organic solvent comprises dimethyl phthalate.

16 . The method of claim 1 wherein the organic solvent concentration in the fluid is from about 10 ppm by weight to about 1% by weight

17 . The method of claim 16 wherein the organic solvent is used to disperse or prevent hydrocarbon foulant from agglomeration, precipitation, or deposition.

18 . The method of claim 17 wherein the organic solvent concentration is from about 100 ppm to about 1000 ppm.

19 . The method of claim 1 wherein the organic solvent is added to the process fluid continuously.

20 . The method of claim 15 wherein the organic solvent concentration is from about 1000 ppm by weight to about 15% by weight

21 . (canceled)

22 . The method of claim 1 wherein the organic solvent is added to the process fluid intermittently.

23 .- 30 . (canceled)

Assignees

• Ecolab Usa Inc

Inventors

• Tong David Youdong

Classifications

• C08F2/005 Primary

  by addition of a scale inhibitor to the polymerisation medium · CPC title

• C07C69/54

  Acrylic acid esters; Methacrylic acid esters · CPC title

• B01J19/002

  Avoiding undesirable reactions or side-effects, e.g. avoiding explosions, or improving the yield by suppressing side-reactions · CPC title

• C07C51/50 Primary

  Use of additives, e.g. for stabilisation · CPC title

• C07C57/04

  Acrylic acid; Methacrylic acid · CPC title