Editing Propylene (section)

===Olefin conversion technology===
In the Phillips triolefin or [[olefin conversion technology]], propylene is interconverted with [[ethylene]] and [[2-butene]]s. [[Rhenium]] and [[molybdenum]] catalysts are used:<ref name="MG">{{cite journal|last1=Ghashghaee|first1=Mohammad|title=Heterogeneous catalysts for gas-phase conversion of ethylene to higher olefins|journal=Rev. Chem. Eng.|volume=34|issue=5|pages=595–655|doi=10.1515/revce-2017-0003|year=2018|s2cid=103664623}}</ref> 
:<chem>CH2=CH2{}  +  CH3CH=CHCH3   ->[][\text{Re, Mo} \atop \text{catalyst}]   2 CH2=CHCH3</chem>

The technology is founded on an [[olefin metathesis]] reaction discovered at [[Phillips Petroleum Company]].<ref>{{cite journal | last1 = Banks | first1 = R. L. | last2 = Bailey | first2 = G. C. | title = Olefin Disproportionation. A New Catalytic Process | journal = Industrial & Engineering Chemistry Product Research and Development | volume = 3 |issue=3| pages = 170–173 | year = 1964 | doi = 10.1021/i360011a002}}</ref><ref name=KO>{{cite encyclopedia|chapter=Metathesis|encyclopedia=Kirk-Othmer Encyclopedia of Chemical Technology|author=Lionel Delaude |author2=Alfred F. Noels |year=2005| doi=10.1002/0471238961.metanoel.a01|place=Weinheim|publisher=Wiley-VCH|isbn=978-0-471-23896-6}}</ref> Propylene yields of about 90 wt% are achieved.

{{main|Syngas to gasoline plus}}
Related is the [[Gas to liquids#Methanol to gasoline (MTG) and methanol to olefins|Methanol-to-Olefins/Methanol-to-Propene]] process. It converts [[Gas to liquids#Syngas to gasoline plus process (STG+)|synthesis gas (syngas)]] to [[methanol]], and then [[Syngas to gasoline plus|converts the methanol to ethylene and/or propene]]. The process produces water as a by-product. [[Synthesis gas]] is produced from the reformation of natural gas or by the steam-induced reformation of petroleum products such as naphtha, or by [[coal gasification|gasification of coal]] or natural gas.