| 摘要 |
<p>977,578. Vinyl chloride. KUREHA KAGAKU KOGYO KABUSHIKI KAISHA. Feb. 22, 1961 [March 4, 1960(4)], No. 6470/61. Drawings to Specification. Heading C2C. Vinyl chloride is obtained from gaseous mixtures produced by thermally cracking hydrocarbons and containing C 2 H 2 , C 2 H 4 , CH 4 , H 2 , CO, CO 2 and higher acetylenic and olefinic hydrocarbons by washing the gas mixture in a scrubbing tower to separate out the higher hydrocarbons, converting the acetylene in the gas into vinyl chloride by reaction with hydrogen chloride in the presence of a hydrochlorination catalyst, contacting the product with dichloroethane in an absorption zone to absorb the vinyl chloride and removing the vinyl chloride/ dichloroethane solution from the lower part of the absorption zone and passing it to a separation tower; removing the ethylene-containing gas from the upper part of the absorption tower and reacting it with chlorine in the presence of dichloroethane as solvent to produce further dichloroethane, venting gas other than ethylene from the upper part of the ethylene reaction zone, removing dichloroethane from the lower part of this zone, thermally decomposing all or a part of the dichloroethane to produce a mixture of vinyl chloride and hydrogen chloride, treating the mixture with dichloroethane in a second separation tower to obtain a solution of vinyl chloride in dichloroethane, recycling this to the first separation tower, and recovering vinyl chloride from the solutions supplied to said tower. The hydrogen chloride separated after the pyrolysis step, which may contain some vinyl chloride, may be recycled to the acetylene hydrochlorination reaction.</p> |
