Abstract: The present invention relates to a process for the producing propylene and ethylene from a light hydrocarbon stream comprising essentially ethane and butane. The process involves a non-catalytic cracking of ethane and normal-butane followed by a metathesis of ethylene and 2-butene to increase the propylene yield. Optionally the by-produced iso-butane is dehydrogenated and subsequently the produced iso-butene is converted to other valuable products like di-isobutylene, alkylate for gasoline blending tertiary-butyl-ethers, poly-isobutylene methyl-metacrylate or isoprene.

Abstract: The present invention relates to a process for the selective production of olefins from light hydrocarbons comprising: a) fractionating a butane fraction in a de-isobutanizer to obtain an enriched iso-butane fraction and an enriched normal-butane fraction, b) cracking said normal-butane fraction and optionally an ethane fraction, optionally a propane fraction, in a non-catalytic cracking zone to produce an olefin rich stream, preferably the ethane fraction, if any, the propane fraction, if any, and normal-butane fractions are cracked in separate non-catalytic cracking zones, c) treating said olefin rich stream in a separating section comprising: removing hydrogen and methane, recovering an ethylene stream, recovering an ethane stream and recycling said stream to the cracking zone, recovering a propylene stream, recovering a propane stream, optionally recycling said stream to the cracking zone, recovering a C4 stream, removing the heavies, d) selectively hydrogenating the dienes and alkynes in the C4 strea