A process for the production of tertiary ethers, including: feeding a
hydrocarbon stream comprising isoolefins and propionitrile to a
distillation column reactor system containing at least one etherification
reaction zone; feeding a C.sub.2 to C.sub.6 monoalcohol or mixture
thereof to the distillation column reactor; concurrently in the
distillation column reactor system: reacting a portion of the isoolefins
with a portion of the alcohols to form a tertiary ether; and separating
the tertiary ether from unreacted isoolefins; withdrawing the tertiary
ether and propionitrile from the distillation column reactor system as a
bottoms; withdrawing the unreacted isoolefins from the distillation
column reactor system as an overheads; and operating the distillation
column reactor system such that the etherification reaction zone is
substantially free of propionitrile.