| 摘要 |
Butadiene free of C3H4 hydrocarbons is separated from pyrolysis gas contg. a major proportion of C1-5 hydrocarbons including butadiene and C3H4 and a minor proportion of C5 - 400 deg.F hydrocarbons by a) introducing the pyrolysis gases into a first separation zone under conditions sufficient to produce one fraction comprising C1-3 hydrocarbons including C3H4 hydrocarbons and another comprising C3+ hydrocarbons contaminated with C3H4 hydrocarbons; b) passing the latter fraction into a second separation zone under conditions sufficient to produce a third fraction comprising C3 and C4 hydrocarbons including butadiene contg. C3H4 contaminant and a fourth fraction comprising C5+ hydrocarbons and c) passing the third fraction into a third separation zone under distillation conditions (including a temp. less than 225 deg.F and a pressure 25-200 psig less than the pressure in the first separation zone) sufficient to produce a C3 fraction contg. contaminant and a C4 fraction contg. butadiene subst. free of contaminant. |
