SEPARATION OF A C.SUB.4-HYDROCARBON MIXTURE ESSENTIALLY CONTAINING N-BUTENES AND BUTANES

摘要

The invention relates to a process for the separation of a C4-hydrocarbon mixture which essentially contains n-butenes and butanes. This process is characterized in that the mixture is reacted with a carboxylic acid in the presence of an acidic catalyst to form a butyl carboxylate; the reaction mixture obtained from the esterification zone is distilled to give, as the top product, a fraction containing the butanes, and, as the bottom product, a fraction containing the resulting butyl carboxylate; the butyl carboxylate is decomposed at elevated temperatures to give the carboxylic acid and n-butenes; and the mixture of n-butenes and carboxylic acid is then distilled, the n-butenes being obtained as the top product, and the carboxylic acid as the bottom product. This process permits to use apparatus that are less expensive than those required for the conventional extractive distillation method.