Production of allyl chloride

• US 3,865,886 A
• Filed: 06/20/1973
• Issued: 02/11/1975
• Est. Priority Date: 06/20/1973
• Status: Expired due to Term

• Current Assignee: Harvey D. Schindler, Herbert Riegel, Morgan C. Sze
• Original Assignee: Harvey D. Schindler, Herbert Riegel, Morgan C. Sze
• Inventors: Sze, Morgan C., Riegel, Herbert, Schindler, Harvey D.
• Primary Examiner(s): Gantz, Delbert E.
• Assistant Examiner(s): Boska, Joseph
• Application Number:
  US05/371,615
• Time in Patent Office: 601 Days
• Field of Search: 260/DIG.42,654A,654R,654D,654H,659A,659R,658R,660
• US Class Current: 570/220
• CPC Class Codes: C07C 17/087 to unsaturated halogenated hydrocarbons
• CPC Class Codes: C07C 17/10 of hydrogen atoms combined with addition of halogens to unsaturated hydrocarbons C07C17/06
• CPC Class Codes: C07C 17/154 of saturated hydrocarbons
• CPC Class Codes: C07C 17/25 by splitting-off hydrogen halides from halogenated hydrocarbons
• CPC Class Codes: C07C 19/01 containing chlorine
• CPC Class Codes: C07C 21/067 Allyl chloride; Methallyl chloride
• CPC Class Codes: Y10S 260/42 Melts used in preparation of non-cyclic aliphatic chloro-, bromo- and iodo-hydrocarbons

Abstract

Propane is chlorinated in the presence of a molten salt to allyl chloride and other chlorinated C3 hydrocarbons. Isomers of allyl chloride are hydrochlorinated to dichloropropanes, and dichloropropane is dehydrochlorinated to allyl chloride and its isomers. Hydrogen chloride generated in the dehydrochlorination is recycled to the hydrochlorination and dehydrochlorination steps.

Claims

1. A PROCESS FOR PRODUCING ALLYL CHLORIDE, COMPRISING:

A. CONTACTING IN A FIRST REACTION ZONE PROPANE AND A MEMBER SELECTED FROM THE GROUP CONSISTING OF CHLORINE, HYDROGEN, CHLORIDE AND MIXTURES THEREOF WITH A MOLTEN MIXTURE COMPRISING THE HIGHER AND LOWER VALENT CHLORIDES OF A MULTIVALENT METAL AND THE OXYCHLORIDE OF THE METAL TO PRODUCE A FIRST EFFLUENT COMPRISING ALLYL CHLORIDE, ISOMERS OF ALLYL CHLORIDE, AND DICHLOROPROPANE;

B. RECOVERING DICHLOROPROPANE AND ISOMERS OF ALLYL CHLORIDE FROM THE FIRST EFFLUENT;

C. INTRODUCING ISOMERS OF ALLYL CHLORDE RECOVERED FROM THE FIRST EFFLUENT INTO A SECOND REACTION ZONE WHEREIN THE ISOMERS ARE HYDROCHLORINATED TO DICHLOROPROPANE BY CONTACT WITH HYDROGEN CHLORIDE;

D. DEHYDROCHLORINATING IN A THIRD REACTION ZONE DICHLOROPROPANE PRODUCED IN THE SECOND REACTION ZONE AND DICHLOROPROPANE RECOVERED FROM THE FIRST EFFLUENT TO PRODUCE A SECOND EFFLUENT COMPRISING ALLYL CHLORIDE, HYDROGEN CHLORIDE AND ISOMERS OF ALLYL CHLORIDE;

E. RECOVERING HYDROGEN CHLORIDE AND ISOMERS OF ALLYL CHLORIDE FROM THE SECOND EFFLUENT;

F. RECYCLING HYDROGEN CHLORIDE RECOVERED FROM THE SECOND EFFLUENT TO AT LEAST ONE OF THE FIRST AND SECOND REACTION ZONES;

G. RECOVERING ALLYL CHLORIDE FROM THE FIRST AND SECOND EFFLUENTS AS PRODUCT;

AND H. RECYCLING ISOMERS OF ALLYL CHLORIDE RECOVERED FROM THE SECOND EFFLUENT TO STEP (C).

2. The process of claim 1 wherein the multivalent metal chloride is selected from the group consisting of copper, chromium, cobalt, manganese and iron.

3. The process of claim 2 wherein the contacting of step (a) is effected at a temperature from about 700*F. to about 950*F.

4. The process of claim 3 wherein hydrogen chloride recovered from the second effluent is passed to the second reaction zone to meet hydrogen chloride requirements therefore, wiTh remaining hydrogen chloride being passed to the first reaction zone.

5. The process of claim 4 wherein molten mixture recovered from the first reaction zone is passed to a fourth reaction zone wherein the molten mixture is contacted with molecular oxygen to produce oxychloride and passing molten mixture, containing oxychloride, from said fourth reaction zone to said first reaction zone.

6. The process of claim 5 wherein the molten mixture, includes, as a melting point depressant, a member selected from the group consisting of the alkali metal chlorides and the heavy metal chlorides of Groups I - IV of the Periodic Table.

7. The process of claim 6 wherein the first effluent further comprises unreacted propane, propylene and propyl chloride which are recovered and recycled to the first reaction zone.

8. The process of claim 7 wherein the melting point depressant is potassium chloride.

9. The process of claim 3 wherein the multivalent metal chloride is copper chloride.

10. A continuous process for producing allyl chloride, comprising:

a. contacting in a first reaction zone propane and a member selected from the group consisting of chlorine, hydrogen chloride and mixtures thereof with a molten mixture comprising cuprous chloride, cupric chloride and copper oxychloride to produce a first effluent comprising allyl chloride, isomers of allyl chloride dichloropropanes, propylene, unreacted propane and propyl chloride;

b. recovering and recycling to the first reaction zone propylene, unreacted propane and propyl chloride from the first effluent;

c. recovering isomers of allyl chloride and dichloropropane from the first effluent;

d. hydrochlorinating in a second reaction zone recovered isomers of allyl chloride with hydrogen chloride to produce dichloropropane;

e. dehydrochlorinating in a third reaction zone dichloropropane recovered from the first effluent and dichloropropane produced in the second reaction zone to produce a second effluent comprising hydrogen chloride, allyl chloride and isomers of allyl chloride;

f. recovering and passing to the second reaction zone isomers of allyl chloride present in the second effluent;

g. recovering and passing to at least one of said first and second reaction zones hydrogen chloride present in the second effluent;

h. recovering as reaction product allyl chloride present in the first and second effluent;

i. contacting melt from the first reaction zone in a fourth reaction zone with molecular oxygen to produce copper oxychloride; and

j. passing melt from the fourth reaction zone to the first reaction zone.

11. The process of claim 10 wherein the first reaction zone is operated at a temperature from about 700*F. to about 950*F.

12. The process of claim 11 wherein the second reaction zone is operated at a temperature from about 100*F. to about 400*F.

13. The process of claim 12 wherein the third reaction zone is operated at a temperature from about 500*F. to about 1,000*F.

14. The process of claim 13 wherein hydrogen chloride recovered from the second effluent is passed to both the first and second reaction zones.

15. The process of claim 14 wherein the molten mixture further comprises, as a melting point depressant, a member selected from the group consisting of the alkali metal chlorides and the heavy metal chlorides of Groups I - IV of the Periodic Table.

16. The process of claim 15 wherein the melting point depressant is potassium chloride.

17. The process of claim 16 wherein the molten mixture contains from about 17% to about 35%, by weight, of cupric chloride.

18. The process of claim 16 wherein the first effluent further comprises at least one C3 chlorinated hydrocarbon substituted with at least three chlorine atoms, recovering and burning said at least one C3 chlorinated hydrocarbon to produce a combustion effluent containing gaseouS chlorine values and introducing the combustion effluent into the fourth reaction zone to recover the gaseous chlorine values.