Metathesis in Oleochemistry
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چکیده
Me tá te se é uma re a ção atra en te para a con ver são de óle os e gor du ras em pro du tos quí mi cos úte is. Assim, a me tá te se de és te res de áci dos gra xos in sa tu ra dos (cons ti tu in tes bá si cos de óle os e gor du ras) é uma rota con ve ni en te para a sín te se de diés te res in sa tu ra dos, que po dem ser usa dos como in ter me diá ri os na pro du ção de po lí me ros e na quí mi ca fina. A me tá te se cru za da com ole fi nas sim ples per mi te al te rar o com pri men to da ca de ia car bo na da de áci dos gra xos e de seus de ri va dos; a me tá te se cru za da com ete no (ete nó li se) for ne ce com pos tos con ten do li ga ções du plas ter mi na is, que pos su em uma ex ten sa gama de apli ca ções. A ete nó li se de óle os gra xos (tri gli ce rí de os) per mi te a trans for ma ção de tri gli ce rí de os de áci dos gra xos de lon gas ca de i as car bo na das em óle os gra xos de me nor mas sa mo le cu lar. Di ver sos sis te mas ca ta lí ti cos ho mo gê ne os ou he te ro gê ne os -, al ta men te se le ti vos, se mos tra ram ca pa zes de efe tu ar a me tá te se de és te res in sa tu ra dos. Ca ta li sa do res he te ro gê ne os à base de rê nio ou de mo lib dê nio têm atra í do mu i ta aten ção. Con si de ran do os pro ce di men tos de ati va ção e de re ge ne ra ção do ca ta li sa dor, os sis te mas ca ta lí ti cos à base de rê nio são pre fe ri dos.
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