ALKYLATION CATALYST REGENERATION

Alkylation process comprises (a) preparing a catalyst by mixing H2O-contg. sulpholane with HF, (b) contacting a hydrocarbon mixt. contg. olefins and isoparaffins with the catalyst to produce alkylate and by-product (acid-soluble oil, ASO), (c) sepg. the alkylate from ASO-contg. catalyst, (d) passing a side stream of the ASO-contg. catalyst to a separator and recycling the rest to step (b), (e) withdrawing an HF- and H2O-contg. overhead stream and a sulpholane- and ASO-contg. bottoms stream from the separator, and (f) condensing the overhead stream and recycling part of the condensate to step (b) while passing the rest to downstream processing at a rate sufficient to maintain an H2O concn. below 10 wt.% in the catalyst stream sepd. in step (c). Pref.,the sulpholane in step (a) contains 0.1-5 wt.% H2O. The wt. ratio of HF to sulpholane is 1.1-40:1. The HF:H2O wt. ratio in the overhead stream from step (e) is 1.01-100:1.