A process for the purification of isobutene from a C4 stream with at least 1-butene, 2-butene, isobutane and isobutene includes isomerizing 1-butene from a stream of material which is concentrated in isobutane and isobutene obtained from the C4 stream into 2-butene, using a catalyst in an isomerization reactor; supplying a product stream from the isomerization reactor to a rectification column; and providing a stream of material which is concentrated in isobutene. A processing facility is utilized for the purification of isobutene from the C4 stream.

A process for the purification of isobutene from a C4 stream with at least 1-butene, 2-butene, isobutane and isobutene includes isomerizing 1-butene from a stream of material which is concentrated in isobutane and isobutene obtained from the C4 stream into 2-butene, using a catalyst in an isomerization reactor; supplying a product stream from the isomerization reactor to a rectification column; and providing a stream of material which is concentrated in isobutene. A processing facility is utilized for the purification of isobutene from the C4 stream.

A method for the production of a fuel additive includes passing a hydrocarbon stream comprising crude mixed C4 hydrocarbons through a first hydrogenation unit to produce a first product stream; passing the first product stream from the first hydrogenation unit to a methyl tert-butyl ether synthesis unit forming methyl tert-butyl ether and a byproduct stream; passing the byproduct stream through a first distillation unit to separate the byproduct stream into a first 1-butene stream, an isobutane stream, and a 2-butene and n-butane stream; forming a second product stream by passing the 2-butene and n-butane stream to a selective conversion unit; passing the second product stream into a second distillation unit to form an n-butane stream and a second 1-butene stream; passing the second 1-butene stream to a fuel additive production unit; and passing the first 1-butene stream to the fuel additive production unit to form the fuel additive.

A method for the production of a fuel additive includes passing a hydrocarbon stream comprising crude mixed C4 hydrocarbons through a first hydrogenation unit to produce a first product stream; passing the first product stream from the first hydrogenation unit to a methyl tert-butyl ether synthesis unit forming methyl tert-butyl ether and a byproduct stream; passing the byproduct stream through a first distillation unit to separate the byproduct stream into a first 1-butene stream, an isobutane stream, and a 2-butene and n-butane stream; forming a second product stream by passing the 2-butene and n-butane stream to a selective conversion unit; passing the second product stream into a second distillation unit to form an n-butane stream and a second 1-butene stream; passing the second 1-butene stream to a fuel additive production unit; and passing the first 1-butene stream to the fuel additive production unit to form the fuel additive.

Processes incorporating a common organic chloride decomposition reactor and chloride treater to be used by both the C.sub.4 and C.sub.5-6 isomerization reaction zones are described. A portion of the C.sub.4 isomerization reaction zone off gas is routed to the C.sub.4 HCl absorber, which provides about 85% of the HCl requirement for the C.sub.4 isomerization reaction zone. A small amount of the C.sub.5-6 isomerization reaction zone off gas is mixed with the C.sub.4 isomerization reaction zone off gas portion going to the C.sub.4 HCl absorber.

Processes incorporating a common organic chloride decomposition reactor and chloride treater to be used by both the C.sub.4 and C.sub.5-6 isomerization reaction zones are described. A portion of the C.sub.4 isomerization reaction zone off gas is routed to the C.sub.4 HCl absorber, which provides about 85% of the HCl requirement for the C.sub.4 isomerization reaction zone. A small amount of the C.sub.5-6 isomerization reaction zone off gas is mixed with the C.sub.4 isomerization reaction zone off gas portion going to the C.sub.4 HCl absorber.

A dividing wall column is used in an alkylation process flow scheme to fractionate an alkylate reactor effluent to produce an iso-butane-rich stream as a recycle feed for the alkylation reactor while also separating iso-butane, normal butane and alkylate as separate product streams depending on the reactor effluent composition. In an optional embodiment, the scheme may contain propane.

A process for producing olefins may include dehydrogenating a first alkane in a first reactor to produce a first effluent comprising at least one of a first n-olefin or a first diolefin; removing the first effluent from the first reactor; and regenerating the first reactor. The first reactor may include a first dehydrogenation catalyst and a first phase change material.

An alkylation process including an upfront isomerization zone is described. 100% n-butane or field butanes can be converted into a blend of approximately 60 wt % isobutane and 40 wt % n-butane in the isomerization zone. This blend can be used as the feed to all types of alkylation zones. It stabilizes the feed composition so that the dehydrogenation zone and alkylation zone always operate with the same feed.

An alkylation process including an upfront isomerization zone is described. 100% n-butane or field butanes can be converted into a blend of approximately 60 wt % isobutane and 40 wt % n-butane in the isomerization zone. This blend can be used as the feed to all types of alkylation zones. It stabilizes the feed composition so that the dehydrogenation zone and alkylation zone always operate with the same feed.