| 摘要 |
1,167,280. Preparation of 1,2-dichloroethane and vinyl chloride. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. 15 May, 1968 [17 May, 1967], No. 23067/68. Heading C2C. 1,2-Dichloroethane is prepared in two stages by oxychlorination of ethylene in a first stage usually at 200-300‹ C. to give 30-65% molar conversion of C 2 H 4 into CH 2 Cl.CH 2 Cl and chlorination by Cl 2 of the remaining C 2 H 4 in a second stage, a catalyst being used in the first stage comprising (a) at least one copper chloride, (b) at least one chloride of a rare earth metal or of Sc, Y, Zr, Th or U, and (c) at least one alkali metal chloride, the atomic ratio of rare earth metal(s) to copper being at least 0À1 : 1. The catalyst may be supported by a porous carrier material and the oxychlorination stage may be carried out in a fluidized catalyst bed. Vinyl chloride is prepared by a three-step integrated process by (1) oxychlorination of C 2 H 4 to obtain 30-65% molar conversion into CH 2 Cl. CH 2 Cl; (2) chlorination of the remaining C 2 H 4 by C1 2 ; and (3) pyrolysis of 1,2-dichloroethane, the HCl from the final step being recycled to the first step and chlorine losses being compensated by addition of Cl 2 and/or HCl and O 2 in the first step and/or Cl 2 in the second step. The oxychlorination step is usually carried out using the catalyst above. |
