PROPYLENE TRIMER AND TETRAMER ISOLATION PROCESS Russian patent published in 2005 - IPC

FIELD: petrochemical processes.

SUBSTANCE: products obtained via oligomerization of propylene on phosphoric acid catalyst are subjected to rectification. Oligomerizate if first fed into first column from which top product containing unreacted hydrocarbon is withdrawn and bottom product is sent into second rectification column. Top product of the second column is constituted by propylene dimer fraction and bottom product of this column is sent into third rectification column. Top product of the third column is constituted by C7-C8-olefin fraction and bottom product of this column is constituted by propylene trimer and tetramer fraction, which is separated into desired products. A part of propylene dimer fraction obtained as top product of the second fraction is passed to reflux first column and to additionally cool bottom product of the first column used as feed for the second column and/or bottom product of the second column used as feed for the third column.

EFFECT: reduced power consumption and increased separation capacity of propylene oligomer isolation column.

2 cl, 1 dwg, 3 ex