Chothandizira champhamvu kwambiri chomwe chimasintha mpweya wa propane kukhala ma hydrocarbon olemera kwambiri chapangidwa ndi King Abdullah University of Science and Technology waku Saudi Arabia. (KAUST) ofufuza. Imafulumizitsa kwambiri mankhwala omwe amadziwika kuti alkane metathesis, omwe angagwiritsidwe ntchito kupanga mafuta amadzimadzi.

Chothandiziracho chimakonzanso propane, yomwe ili ndi maatomu atatu a kaboni, kukhala mamolekyu ena, monga butane (okhala ndi ma carbon anayi), pentane (yokhala ndi ma carbons asanu) ndi ethane (yokhala ndi ma carbons awiri). "Cholinga chathu ndikusintha ma alkanes ocheperako kukhala ma alkanes ofunika kwambiri," atero a Manoja Samantaray ochokera ku KAUST Catalysis Center.

Pamtima pa chothandiziracho pali zitsulo ziwiri, titaniyamu ndi tungsten, zomwe zimakhazikika pamtunda wa silica kudzera mwa maatomu a okosijeni. Njira yomwe idagwiritsidwa ntchito inali catalysis ndi mapangidwe. Kafukufuku wam'mbuyomu adawonetsa kuti zothandizira za monometallic zidagwira ntchito ziwiri: alkane kupita ku olefin ndiyeno olefin metathesis. Titaniyamu idasankhidwa chifukwa cha kuthekera kwake kuyambitsa chomangira cha CH cha parafini kuti chisinthe kukhala olefins, ndipo tungsten idasankhidwa chifukwa cha ntchito yake yayikulu ya olefin metathesis.

Kuti apange chothandizira, gululo linatenthetsa silika kuti lichotse madzi ambiri momwe angathere ndikuwonjezera hexamethyl tungsten ndi tetraneopentyl titaniyamu, kupanga ufa wonyezimira wachikasu. Ofufuzawo adafufuza chothandizira pogwiritsa ntchito mawonekedwe a nyukiliya maginito (NMR) kuwonetsa kuti ma atomu a tungsten ndi titaniyamu amakhala pafupi kwambiri pamalo a silika, mwina pafupi ndi ≈0.5 nanometres.

Ofufuzawo, motsogozedwa ndi Mtsogoleri wa likulu la Jean-Marie Basset, adayesa chothandizira pochiwotcha mpaka 150 ° C ndi propane kwa masiku atatu. Atatha kuwongolera momwe zinthu zimayendera - mwachitsanzo, polola kuti propane ikuyenda mosalekeza pa chothandiziracho - adapeza kuti zinthu zazikulu zomwe zidachitikazo zinali ethane ndi butane komanso kuti ma atomu a tungsten ndi titaniyamu amatha kuyambitsa mizungu 10,000 m'mbuyomu. kutaya ntchito zawo. "Nambala yobweza" iyi ndiyokwera kwambiri yomwe idanenedwapo chifukwa cha propane metathesis reaction.

Kupambana kumeneku kwa catalysis ndi mapangidwe, ofufuzawo akuganiza, chifukwa cha mgwirizano womwe ukuyembekezeka pakati pa zitsulo ziwirizi. Choyamba, atomu ya titaniyamu imachotsa maatomu a haidrojeni ku propane kupanga propene ndiyeno atomu ya tungsten yoyandikana nayo imathyola pulopeni yotseguka pamabondi ake a carbon-carbon double, kupanga tizidutswa tomwe tingagwirizanenso kukhala ma hydrocarbon ena. Ofufuzawo adapezanso kuti zopangira ufa zomwe zimakhala ndi tungsten kapena titaniyamu zokha sizinachite bwino kwambiri; ngakhale pamene ufa awiriwa adasakanikirana pamodzi, machitidwe awo sanagwirizane ndi chothandizira chogwirizanitsa.

Gululi likuyembekeza kupanga chothandizira chabwinoko chokhala ndi chiwerengero chochulukira, komanso moyo wautali. "Tikukhulupirira kuti posachedwapa, makampani atha kutengera njira yathu yopangira ma alkanes osiyanasiyana a dizilo komanso njira zambiri zopangira zida," adatero Samantaray.