Indasitiri yemapurisa indasitiri indasitiri yemakemikari inogadzirisa mafuta asina kuchena mafuta, gasi rechisikigo uye zvimwe zvinhu zvakasarudzika muholi, peturu, rubber, makemikari uye zvimwe zvigadzirwa zvekutengesa. Gasi Maindasitiri uye Gasi rakawanda rinotamba basa rakakosha mune iyi indasitiri. Acetylene, ethylene, procylene, butene, butadiene uye mamwe magasi maindasitiri ndizvo zvinhu zvekutanga zvezvinyorwa zvechipfumbamwe zveindasitiri yechipfuva.