A method for producing a blended jet boiling range composition stream may include: oligomerizing an ethylene stream to a C4+ olefin stream in a first olefin oligomerization unit, wherein the C4+ olefin stream contains no greater than 10 wt % of methane, ethylene, and ethane combined; wherein the ethylene stream contains at least 50 wt % ethylene, at least 2000 wppm ethane, no greater than 1000 wppm of methane, and no greater than 20 wppm each of carbon monoxide and hydrogen; oligomerizing the C4+ olefin stream and a propylene/C4+ olefin stream in a second oligomerization unit to produce an isoolefinic stream; subjecting at least a portion of the isoolefinic stream to a hydroprocessing process with hydrogen as treat gas to produce an isoparaffinic stream having no greater than 10 wt % olefin content; and using least a portion of the isoparaffinic stream to create the blended jet boiling range.

A method for producing a blended jet boiling range composition stream may include: oligomerizing an ethylene stream to a C4+ olefin stream in a first olefin oligomerization unit, wherein the C4+ olefin stream contains no greater than 10 wt % of methane, ethylene, and ethane combined; wherein the ethylene stream contains at least 50 wt % ethylene, at least 2000 wppm ethane, no greater than 1000 wppm of methane, and no greater than 20 wppm each of carbon monoxide and hydrogen; oligomerizing the C4+ olefin stream and a propylene/C4+ olefin stream in a second oligomerization unit to produce an isoolefinic stream; subjecting at least a portion of the isoolefinic stream to a hydroprocessing process with hydrogen as treat gas to produce an isoparaffinic stream having no greater than 10 wt % olefin content; and using least a portion of the isoparaffinic stream to create the blended jet boiling range.

A method of producing a fuel additive includes passing a feed stream comprising C4 hydrocarbons through a hydrogenation unit producing a hydrogenated stream; passing the hydrogenated stream through a distillation unit producing a first stream and a second stream; producing an isobutylene stream by passing the first stream through a molecular sieve unit; passing the isobutylene stream to a hydration unit as a feedstock for the fuel additive; and forming the fuel additive in the hydration unit.

A method of producing a fuel additive includes passing a feed stream comprising C4 hydrocarbons through a hydrogenation unit producing a hydrogenated stream; passing the hydrogenated stream through a distillation unit producing a first stream and a second stream; producing an isobutylene stream by passing the first stream through a molecular sieve unit; passing the isobutylene stream to a hydration unit as a feedstock for the fuel additive; and forming the fuel additive in the hydration unit.

Processes and systems for making recycle content hydrocarbons, including olefins, from recycled waste material. Recycle waste material may be pyrolyzed to form recycle content pyrolysis oil composition (r-pyoil), at least a portion of which may then be cracked to form a recycle content olefin composition (r-olefin). The r- olefin may then be further separated into product streams in a separation zone downstream of the cracker furnace. In some cases, presence of recycle content hydrocarbons may facilitate more efficient operation of one or more distillation columns in the separation zone, including the demethanizer.

Processes and systems for making recycle content hydrocarbons, including olefins, from recycled waste material. Recycle waste material may be pyrolyzed to form recycle content pyrolysis oil composition (r-pyoil), at least a portion of which may then be cracked to form a recycle content olefin composition (r-olefin). The r- olefin may then be further separated into product streams in a separation zone downstream of the cracker furnace. In some cases, presence of recycle content hydrocarbons may facilitate more efficient operation of one or more distillation columns in the separation zone, including the demethanizer.

Systems and methods for producing propylene using an MTBE synthesis raffinate are disclosed. An MTBE synthesis raffinate stream first passes through a molecular sieve to separate n-butane and isobutane from the rest of C.sub.4 hydrocarbons of the MTBE synthesis raffinate. The 1-butene in the rest of C.sub.4 hydrocarbons of the MTBE synthesis raffinate is then isomerized to form 2-butene. Therefore, the concentration of 2-butene in the subsequent propylene production process increases due to the separation of n-butane and isobutane and the isomerization of 1-butene, resulting in an improved reaction rate and reaction efficiency for propylene production.

Systems and methods for producing propylene using an MTBE synthesis raffinate are disclosed. An MTBE synthesis raffinate stream first passes through a molecular sieve to separate n-butane and isobutane from the rest of C.sub.4 hydrocarbons of the MTBE synthesis raffinate. The 1-butene in the rest of C.sub.4 hydrocarbons of the MTBE synthesis raffinate is then isomerized to form 2-butene. Therefore, the concentration of 2-butene in the subsequent propylene production process increases due to the separation of n-butane and isobutane and the isomerization of 1-butene, resulting in an improved reaction rate and reaction efficiency for propylene production.

Systems and methods for producing propylene using an MTBE synthesis raffinate are disclosed. An MTBE synthesis raffinate stream first passes through a molecular sieve to separate n-butane and isobutane from the rest of C.sub.4 hydrocarbons of the MTBE synthesis raffinate. The 1-butene in the rest of C.sub.4 hydrocarbons of the MTBE synthesis raffinate is then isomerized to form 2-butene. Therefore, the concentration of 2-butene in the subsequent propylene production process increases due to the separation of n-butane and isobutane and the isomerization of 1-butene, resulting in an improved reaction rate and reaction efficiency for propylene production.

Systems and processes disclosed may be used to produce a high purity isobutane stream and a high purity 1-butene stream from mixed C4 streams having disparate starting compositions.