# US 5,705,721 A · Dispersant for chloroprene unit fouling

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- Number: US 5,705,721 A
- Document ID: US5705721A
- Status: Granted
- Kind: A
- Application number: 08/743,016
- Filed: 1996-11-01
- Granted: 1998-01-06
- Earliest claimed: 1996-01-19
- Assignees: Nalco Chemical Company
- Inventors: Natu R. Patel
- Web page: https://patentgrep.com/patent/US5705721A

## CPC

- C07C 17/42: Use of additives, e.g. for stabilisation
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS

## Abstract

The present invention provides a method for inhibiting fouling deposits in chloroprene production units. The deposits are inhibited by addition to the chloroprene feedstock of an effective amount of a dispersant prepared in accordance with this invention. The dispersants comprise imides which are prepared by reacting substituted succinic anhydrides with amines.

## Claims

### Claim 1

A method of inhibiting the formation of foulant deposits on the surfaces of processing equipment in contact with a chloroprene process stream during chloroprene recovery which comprises adding to the liquid or gaseous phases of said stream an effective antifouling amount of a dispersant which is a polyalkenylsuccinimide having the formula: ##STR15## wherein R is an aliphatic alkenyl or alkyl moiety having at least about 50 carbon atoms and less than about 200 carbon atoms, Q is a divalent aliphatic radical, n is a positive integer, A is hydrocarbyl, hydroxyalkyl or hydrogen, Z is H or ##STR16##

### Claim 2 (depends on 1)

The method of claim 1 wherein the dispersant is added in from about 10 to about 20,000 ppm by weight.

### Claim 3 (depends on 1)

The method of claim 1 wherein the dispersant is added in from about 50 to about 10,000 ppm by weight.

### Claim 4 (depends on 1)

The method of claim 1 wherein the dispersant is added in from about 100 to about 1,000 ppm by weight.

### Claim 5 (depends on 1)

The method of claim 1 wherein the dispersant is dissolved in a hydrocarbon solvent prior to addition to the chloroprene process stream.

### Claim 6 (depends on 1)

The method of claim 1 wherein R comprises more than 50 carbon atoms and is a polyalkenyl moiety and Z is ##STR17##

### Claim 7 (depends on 6)

The method of claim 6 wherein R comprises a repeated isobutenyl moiety.

### Claim 8 (depends on 7)

The method of claim 7 wherein Q is chosen from C.sub.1 -C.sub.5 alkylene and A is hydrogen.

### Claim 9 (depends on 8)

The method of claim 8 wherein Q is ethylene.

### Claim 10 (depends on 9)

The method of claim 9 wherein R has a molecular weight of about 1300.

### Claim 11

A method of inhibiting the formation of foulant deposits on the surfaces of processing equipment in contact with a chloroprene process stream during chloroprene recovery which comprises adding to the liquid or gaseous phases of said stream an effective antifouling amount of a dispersant which is a polyalkenylsuccinimide having the formula: ##STR18## wherein R is an aliphatic alkenyl or alkyl moiety having at least about 50 carbon atoms and less than about 200 carbon atoms, Q is a divalent aliphatic radical, n is a positive integer, A is hydrocarbyl, hydroxyalkyl or hydrogen, Z is H or ##STR19##

### Claim 12 (depends on 11)

The method of claim 11 wherein the dispersant is added in from about 10 to about 20,000 ppm by weight.

### Claim 13 (depends on 11)

The method of claim 11 wherein the dispersant is added in from about 50 to about 10,000 ppm by weight.

### Claim 14 (depends on 11)

The method of claim 11 wherein the dispersant is added in from about 100 to about 1,000 ppm by weight.

### Claim 15 (depends on 11)

The method of claim 11 wherein the dispersant is dissolved in a hydrocarbon solvent prior to addition to the chloroprene process stream.

### Claim 16 (depends on 11)

The method of claim 11 wherein R comprises more than 50 carbon atoms and is a polyalkenyl moiety and Z is ##STR20##

### Claim 17 (depends on 16)

The method of claim 16 wherein R comprises a repeated isobutenyl moiety.

### Claim 18 (depends on 17)

The method of claim 17 wherein Q is ethylene.

### Claim 19 (depends on 18)

The method of claim 18 wherein R has a molecular weight of about 1300.