Patent ID: 6225516
Filing Date: 2001-05-01
Classification: C07C

Abstract:
A process for producing linear alkylaromatic hydrocarbons containing from 10 to 14 carbon atoms in the alkyl chain, comprising the steps of:(a) dehydrogenating C.sub.10 -C.sub.14 n-paraffins to the corresponding n-olefins in a dehydrogenation reactor to obtain a mixture comprising said n-olefins, diolefins, aromatic by-products;(b) selectively hydrogenating said diolefins into mono-olefins, to obtain a mixture comprising said n-olefins said mono-olefins, n-paraffins, and said aromatic by-products;(c) feeding said mixture in step (b), together with a stream consisting of an aromatic hydrocarbon, to an alkylation unit in which an alkylation catalyst is present and alkylating to obtain an alkylation product;(d) distilling said alkylation product to obtain a fraction comprising said aromatic hydrocarbon, a paraffinic fraction consisting essentially of C.sub.10 -C.sub.14 n-paraffins and said aromatic by-products, and a fraction comprising said linear alkylaromatic hydrocarbons, respectively;(e) subjecting said paraffinic fraction to a hydrogenation step to transform the aromatic by-products into cycloparaffins;(f) recycling said cycloparaffins in step (e) to the dehydrogenation reactor of step (a).