A method for producing hydrocarbons is proposed wherein a catalysis product stream (b) rich in n-butane, isobutane, 1-butene, 2-butene, isobutene and hydrocarbons with more than four and/or less than four carbon atoms is produced in a catalysis unit (1), using one or more catalyst feed streams containing oxygenates and/or olefins (a) and wherein additionally a steam cracking product stream (h) is produced in a steam cracking unit (2) using one or more steam cracking feed streams (g, r, s). It is provided that using the catalysis product stream (b) a skeletal isomerisation feed stream (f, q) poor in 1-butene, 2-butene and isobutene and containing at least isobutane is produced, in which the isobutane is at least predominantly reacted by skeletal isomerisation to form n-butane, and which is subsequently used at least partly as the, or one of the, steam cracking feed streams (g, r). The invention also relates to an apparatus (100, 200).

A method for producing hydrocarbons is proposed wherein a catalysis product stream (b) rich in n-butane, isobutane, 1-butene, 2-butene, isobutene and hydrocarbons with more than four and/or less than four carbon atoms is produced in a catalysis unit (1), using one or more catalyst feed streams containing oxygenates and/or olefins (a) and wherein additionally a steam cracking product stream (h) is produced in a steam cracking unit (2) using one or more steam cracking feed streams (g, r, s). It is provided that using the catalysis product stream (b) a skeletal isomerisation feed stream (f, q) poor in 1-butene, 2-butene and isobutene and containing at least isobutane is produced, in which the isobutane is at least predominantly reacted by skeletal isomerisation to form n-butane, and which is subsequently used at least partly as the, or one of the, steam cracking feed streams (g, r). The invention also relates to an apparatus (100, 200).

A process for producing ethylene and at least one of butanol and an alkyl tert-butyl ether from field butane includes separating the field butane into an n-butane stream and an isobutane stream; cracking the n-butane stream to obtain a cracked product stream comprising n-butane, 1-butene, 2-butene, butadienes, or a combination comprising at least one of the foregoing; and at least one of the following: (1) separating the cracked product stream to obtain a butane stream and a butene stream, and reacting the butene stream with water to obtain a fuel additive comprising butanol, and (2) dehydrogenating the isobutane stream in a dehydrogenation unit to form an isobutene stream and reacting the isobutene stream with an aliphatic alcohol to produce an alkyl tert-butyl ether.

A process for producing ethylene and at least one of butanol and an alkyl tert-butyl ether from field butane includes separating the field butane into an n-butane stream and an isobutane stream; cracking the n-butane stream to obtain a cracked product stream comprising n-butane, 1-butene, 2-butene, butadienes, or a combination comprising at least one of the foregoing; and at least one of the following: (1) separating the cracked product stream to obtain a butane stream and a butene stream, and reacting the butene stream with water to obtain a fuel additive comprising butanol, and (2) dehydrogenating the isobutane stream in a dehydrogenation unit to form an isobutene stream and reacting the isobutene stream with an aliphatic alcohol to produce an alkyl tert-butyl ether.

Systems and methods for processing a C.sub.3 and C.sub.4 hydrocarbon mixture have been disclosed. The C.sub.3 and C.sub.4 hydrocarbon mixture is first processed in an isomerization unit to isomerize n-butane to form isobutane. The resulting effluent stream from the isomerization unit comprising primarily isobutane and C.sub.3 hydrocarbons, collectively, is flowed into a separation unit configured to separate the effluent stream to form a C.sub.3 stream comprising C.sub.1 to C.sub.3 hydrocarbons and a C.sub.4 stream comprising primarily isobutane. The isobutane in the C.sub.4 stream is further dehydrogenated to form isobutene, which is further flowed into an MTBE synthesis unit as a feedstock for producing MTBE.

Systems and methods for processing a C.sub.3 and C.sub.4 hydrocarbon mixture have been disclosed. The C.sub.3 and C.sub.4 hydrocarbon mixture is first processed in an isomerization unit to isomerize n-butane to form isobutane. The resulting effluent stream from the isomerization unit comprising primarily isobutane and C.sub.3 hydrocarbons, collectively, is flowed into a separation unit configured to separate the effluent stream to form a C.sub.3 stream comprising C.sub.1 to C.sub.3 hydrocarbons and a C.sub.4 stream comprising primarily isobutane. The isobutane in the C.sub.4 stream is further dehydrogenated to form isobutene, which is further flowed into an MTBE synthesis unit as a feedstock for producing MTBE.

Methods and systems for steam cracking a mixed butane containing feed stream are disclosed. The feed stream includes n-butane and isobutane. The disclosed methods and systems entail splitting the feed into an enriched n-butane fraction and an enriched isobutane fraction. The enriched n-butane fraction is provided to the cracking furnaces, which yield the olefin products and also yield C4 species. The C4 species are partially hydrogenated and provided as a reactant feed to an alkylation reaction. The enriched isobutane fraction is also provided to the alkylation reaction, whereby high value alkylate product is produced. The disclosed methods and systems have increase olefins (especially ethylene) yield because the feed to the cracking process is enriched in n-butane. The economics are also improved because high value alkylate product is produced from a portion of the isobutane.

Methods and systems for steam cracking a mixed butane containing feed stream are disclosed. The feed stream includes n-butane and isobutane. The disclosed methods and systems entail splitting the feed into an enriched n-butane fraction and an enriched isobutane fraction. The enriched n-butane fraction is provided to the cracking furnaces, which yield the olefin products and also yield C4 species. The C4 species are partially hydrogenated and provided as a reactant feed to an alkylation reaction. The enriched isobutane fraction is also provided to the alkylation reaction, whereby high value alkylate product is produced. The disclosed methods and systems have increase olefins (especially ethylene) yield because the feed to the cracking process is enriched in n-butane. The economics are also improved because high value alkylate product is produced from a portion of the isobutane.

A method for processing pentanes obtained from a DIB unit is disclosed. The process can include separating a first stream containing pentanes obtained from a DIB unit, in a separation column to obtain a second stream comprising iso-pentane and a third stream comprising n-pentane and neo-pentane; and subjecting the third stream to a butane isomerization unit producing a fourth stream containing iso-pentane, n-pentane, and neo-pentane.

A method for processing pentanes obtained from a DIB unit is disclosed. The process can include separating a first stream containing pentanes obtained from a DIB unit, in a separation column to obtain a second stream comprising iso-pentane and a third stream comprising n-pentane and neo-pentane; and subjecting the third stream to a butane isomerization unit producing a fourth stream containing iso-pentane, n-pentane, and neo-pentane.