Process for converting olefins to jet fuel
A process for dimerizing and oligomerizing olefins to distillate fuels which subjects oligomerized product to hydrocracking and hydroisomerization in a single reactor to convert heavier oligomers to jet fuel range oligomers. A jet fuel product stream may be taken from a side of a stripping column which produces a heavy drag stream from a bottom of the stripping column to ensure an end point boiling specification is achieved.
1 . A process for oligomerizing an olefin stream comprising:
dimerizing said olefin stream with a first-stage oligomerization catalyst to produce a first- stage oligomerized olefin stream;
oligomerizing said first-stage oligomerized olefin stream with a second-stage oligomerization catalyst to provide a second-stage oligomerized stream;
feeding said oligomerized stream to a jet fuel optimization reactor comprising a cracking catalyst and a hydroisomerization catalyst; and
cracking and hydroisomerizing said second-stage oligomerized stream to provide a cracked oligomerized stream.
2 . The process of claim 1 further comprising hydrogenating said second-stage oligomerized olefin stream before cracking said second-stage oligomerized stream.
3 . The process of claim 1 further comprising separating said second-stage oligomerized stream into a light oligomerized stream and a heavy oligomerized stream and cracking said heavy oligomerized stream.
4 . The process of claim 3 further comprising hydrogenating said heavy oligomerized stream before cracking said heavy oligomerized stream.
5 . The process of claim 1 wherein the amount of said cracking catalyst is greater than about 5 wt % and the amount of said hydroisomerization catalyst is less than about 95 wt %.
6 . The process of claim 1 further comprising separating said cracked oligomerized stream to provide a vaporous cracked oligomerized stream and a liquid cracked oligomerized stream.
7 . The process of claim 6 further comprising stripping said liquid cracked oligomerized stream to provide a green jet stream.
8 . The process of claim 7 further comprising recycling a portion of said green jet stream to said dimerizing step.
9 . The process of claim 7 further comprising stripping said liquid cracked oligomerized stream to provide a heavy drag stream.
10 . The process of claim 8 further comprising cooling and separating said vaporous cracked oligomerized stream to provide a cold vaporous cracked oligomerized stream and a cold liquid cracked oligomerized stream and stripping said cold liquid cracked oligomerized stream with said liquid oligomerized stream.
11 . A process for oligomerizing an olefin stream comprising:
dimerizing said olefin stream with a first-stage oligomerization catalyst to produce a first-stage oligomerized olefin stream;
oligomerizing said first-stage oligomerized olefin stream with a second-stage oligomerization catalyst to provide a second-stage oligomerized olefin stream;
hydrogenating said second-stage oligomerized olefin stream to provide a hydrogenated oligomerized stream;
feeding said oligomerized stream to a jet fuel optimization reactor comprising a cracking catalyst and a hydroisomerization catalyst; and
cracking and hydroisomerizing said hydrogenated oligomerized stream to provide a cracked oligomerized stream.
12 . The process of claim 11 further comprising separating said second-stage oligomerized olefin stream into a light oligomerized olefin stream and a heavy oligomerized olefin stream and hydrogenating said heavy oligomerized olefin stream.
13 . The process of claim 11 wherein the amount of said cracking catalyst in said jet fuel optimization reactor is greater than about 5 wt% and the amount of said hydroisomerization catalyst is less than about 95 wt%.
14 . The process of claim 11 further comprising separating said cracked oligomerized stream to provide a vaporous cracked oligomerized stream and a liquid cracked oligomerized stream.
15 . The process of claim 14 further comprising stripping said liquid cracked oligomerized olefin stream to provide a green jet stream.
16 . The process of claim 15 further comprising recycling a portion of said green jet stream to said dimerizing step.
17 . The process of claim 7 further comprising stripping said liquid cracked oligomerized stream to provide a heavy drag stream.
18 . The process of claim 8 further comprising cooling and separating said vaporous cracked oligomerized stream to provide a cold vaporous cracked oligomerized stream and a cold liquid vaporous cracked oligomerized stream and stripping said cold liquid cracked oligomerized stream with said liquid oligomerized stream.
19 . A process for oligomerizing an olefin stream comprising:
dimerizing said olefin stream with a first-stage oligomerization catalyst to produce a first- stage oligomerized olefin stream;
oligomerizing said first-stage oligomerized olefin stream with a second-stage oligomerization catalyst to provide a second-stage oligomerized olefin stream;
hydrogenating said second-stage oligomerized olefin stream to provide a hydrogenated oligomerized stream;
feeding said oligomerized stream to a jet fuel optimization reactor comprising a cracking catalyst and a hydroisomerization catalyst; and
cracking and isomerizing said hydrogenated oligomerized stream to provide a cracked oligomerized stream.
20 . The process of claim 19 further comprising separating said second-stage oligomerized olefin stream into a light oligomerized olefin stream and a heavy oligomerized olefin stream and hydrogenating said heavy oligomerized olefin stream.