Claims
- 1. In the process for the manufacture of vinyl chloride by pyrolytic decomposition of 1,2-dichloroethane in a furnace with a coiled up reaction tube, the furnace having a convection, a vaporization, a heating and a cracking zone from top to bottom and having upper and lower rows of burners, separating high-boiling constituents from 1,2-dichloroethane in a column preceding the furnace, passing the 1,2-dichloroethane through the reaction tube from top to bottom both the convection and the vaporizing zones being above the upper rows of burners carrying out the pyrolysis at a temperature of 480.degree. C. to 510.degree. C., separating hydrogen chloride and subsequently vinyl chloride from the cracked gas by distillation, recycling the sump product of the vinyl chloride separation to the column preceding the furnace while adding gaseous chlorine in the absence of a catalyst to the recycled sump product, the improvement which comprises using a reaction tube having an internal diameter of from 12 to 16 cm, and supplying through the upper rows of burners an amount of heat that is 1.8 to 2.2 times the amount of heat supplied through the lower rows of burners whereby rapid clogging by carbonization is prevented and operating periods are prolonged.
- 2. The process as set forth in claim 1, wherein the unsaturated by-products formed in the pyrolysis are transformed into chlorination products by treating them with gaseous chlorine.
- 3. The process of claim 2, wherein the unsaturated by-products having double bonds are treated with 20 to 80% of the stoichiometrically required amount of gaseous chlorine required to saturate all of the bonds present in the by-products.
- 4. In the process for the manufacture of vinyl chloride by pyrolytic decomposition of 1,2-dichloroethane in a furnace with a coiled up reaction tube, the furnace having a convection, a vaporization, a heating and a cracking zones from top to bottom and having a plurality of burner rows from top to bottom, both the convection zone and the vaporization zone being above the top row of burners and both the heating zone and the cracking zone being in that part of the furnace where the burner rows are situated, separating high-boiling constituents from 1,2-dichloroethane in a column preceding the furnace, passing the 1,2-dichloroethane through the reaction tube from top to bottom, carrying out the pyrolysis at a temperature of 480.degree. to 510.degree., separating hydrogen chloride and subsequently vinyl chloride from the cracked gas by distillation, recycling the sump product of the vinyl chloride separation to the column preceding the furnace while adding gaseous chlorine in the absence of a catalyst to the recycled sump product, the improvement which comprises using a reaction tube having an internal diameter of from 12 to 16 cm, and supplying through the rows of burners in the heating zone an amount of heat that is 1.8 to 2.2 times the amount of heat supplied through the rows of burners in the cracking zone whereby rapdi clogging by carbonization is prevented and operating periods are prolonged.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2416786 |
Apr 1974 |
DEX |
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CROSS REFERENCE TO RELATION APPLICATIONS
This application is a continuation of Ser. No. 564,038, filed Apr. 1, 1975 by the same inventors, now abandoned.
US Referenced Citations (3)
Foreign Referenced Citations (3)
Number |
Date |
Country |
586326 |
Nov 1959 |
CAX |
938824 |
Oct 1963 |
GBX |
1186742 |
Apr 1970 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
564038 |
Apr 1975 |
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