Simulated moving bed reaction process

Claim 1

A continuous fixed bed catalytic alkylation reaction and catalyst reactivation process comprising the steps of: a. providing a fixed bed of solid catalyst containing four zones having a fluid flow connecting path between said zones to interconnect said zones; b. arranging said zones in a series and providing fluid flow connecting means between the last zone and the first zone of the series to provide a directional circular flow path through said zones; c. providing a point between each two successive zones for introducing an inlet stream or withdrawing a product stream; d. introducing a reactivation stream including alkylatable hydrocarbon at a first point located between two successive zones (zone II and zone III) to effect catalyst reactivation and to provide alkylatable hydrocarbon as a continuous component throughout said fixed bed of solid catalyst; e. simultaneously withdrawing a first product stream from a second point located between said zone III and the next successive zone in the direction of flow (zone IV); f. simultaneously introducing reactants consisting essentially of isobutane, isopentane or a mixture thereof and at least one C 2 - C 5 olefin into said fixed bed of catalyst at a third point located between said zone IV and the next successive zone in the direction of flow (zone I) and reacting said reactants at a temperature of about 100° F to 400° F to effect an alkylation reaction, a result of which is deactivation of said catalyst, said alkylation and catalyst reactivation being the principal reactions of the process; g. simultaneously withdrawing a second product stream from a fourth point located between said zone I and the next successive zone in the direction of flow (zone II); and, h. periodically advancing downstream the points of charging said reactants and said reactivation stream, and the points of withdrawal of said product streams to the next successive points for introducing an inlet stream or withdrawing an outlet stream.