ALKYLATION ACID RECOVERY PROCESS WITH ELIMINATION OF INERT HYDROCARBONS

摘要

Process for recovering used sulfuric acid alkylation catalyst and eliminating normal paraffin hydrocarbons from olefin feed stocks for alkylation. Used sulfuric acid catalyst from an alkylation unit is reacted in a first absorber with a first portion of olefin feed employing a stoichiometric excess of acid for substantially complete conversion of olefin to alkyl sulfate. Unreacted paraffin hydrocarbons are separated from the resulting reaction mixture and removed. The acid phase from the first absorber is extracted with isoparaffin hydrocarbon being alkylated and the raffinate acid therefrom is sent to a second absorber wherein the raffinate acid is reacted with a second portion of olefin feed employing a stoichiometric excess of olefin for substantially complete conversion of the free acid and alkyl acid sulfates to dialkyl sulfates. The dialkyl sulfates are then separated and passed to the alkylation unit. Unreacted olefinic hydrocarbons are separated from the reaction mixture and passed to either the first or second absorber.