Etherification process with sorptive treating of hydrocarbon recycle stream

Claim 1

A process for the production of methyl tertiary butyl ether which comprises the steps of: (a) contacting methanol and a mixed hydrocarbon stream comprising normal butane, isobutane and isobutylene with an acidic etherification catalyst to result in the production of methyl tertiary butyl ether, which is removed in a product stream and a recycle stream comprising isobutane, normal butene, water, butadiene, methanol and methyl tertiary butyl ether; (b) withdrawing said recycle stream, which is rich in C 4 hydrocarbons, and comprises said isobutane, normal butene, water, butadiene, methanol and methyl tertiary butyl ether from the etherification zone; (c) contacting said recycle stream with a sorbent solid selected from the group consisting of a Type 5A and Type 13X molecular sieve to remove said methanol and methyl tertiary butyl ether from the recycle stream; (d) separating said recycle stream in a deisobutanizer into at least a first stream comprising isobutane which is passed into a dehydrogenation zone to produce isobutylene, said isobutylene being passed into said etherification zone of step (a); and, (e) intermittently regenerating said Type 5A or Type 13X molecular sieve by contact with a regeneration gas stream consisting essentially of at least 85 mole percent hydrogen at an initial temperature of below 200° F. and gradually increasing said contact temperature at a rate less than about 50° F. until a temperature in excess of about 400° to 600° F. is reached.