Producing Ethylene from Natural Gas via the Synthesis and Subsequent Pyrolysis of Methyl Chloride: Increasing Selectivity by Introducing a Stage of Polychloromethane Hydrodechlorination

摘要

Comparative tests of palladium, nickel-molybdenum, and lanthanum-magnesium-nickel catalyst samples with aluminium oxide are performed to select an effective catalyst for the hydrodechlorination of methylene chloride and chloroform. The tests are conducted in a flow reactor with a fixed catalyst layer at 300°C with a contact time of 3.8 s and a hydrogen-to-methylene chloride molar ratio of 3 : 1. The nickel- molybdenum catalyst is found to be the one most effective. Improvements to the technological process scheme for the priority production of ethylene to be used in obtaining vinyl chloride are proposed. These improvements require the production of ethylene via an additional stage of the pyrolysis of methane homologues isolated from natural gas and formed in the pyrolysis of methyl chloride, along with a stage of polychloromethane hydrodechlorination.