METHOD OF SEPARATE AND/OR COMBINED PRODUCTION OF ACETYLENE AND ALLENE Russian patent published in 1998 - IPC

FIELD: petrochemical syntheses. SUBSTANCE: acetylene and allene are produced from C₃-hydrocarbon fraction by extractive rectification in presence of acetonitrile as selective solvent. In the first stage of process, under extractive rectification conditions at elevated pressure, propane-propylene fraction is separated until residual content of propane and propylene in C₃ fraction 0.1 to 35% is attained providing phlegmatization of distillate fraction. Subsequent separation of vat product of extractive rectification is performed preferably either in presence of acetonitrile or with no solvent feed to produce allene or allene together with methylacetylene and vat product acetonitrile extract of methylacetylene or methylacetylene-allene fraction. Accuracy of taking off all distillate fractions is controlled by feeding solvent and/or phlegm. Acetonitrile is regenerated by drying and/or rectification. EFFECT: increased purity of products and increased recovery (99%). 3 cl, 1 dwg, 2 tbl, 5 ex