Feedstock preparation of olefins for oligomerization to produce fuels

A method of making a hydrocarbon composition comprising:

• a) providing a first feedstock containing olefins comprising at least 1.0 wt % butenes, at least 1.0 wt % pentenes, and at least 1.0 wt. % hexenes, and containing a first content of dienes that is greater than 4000 wppm, such that the dienes comprise at least 10 wppm of a C4 diene and at least 10 wppm of a C5 diene, and no greater than 2.0 wt % of oxygenates;
• b) contacting the first feedstock with a hydrogenation catalyst in the presence of hydrogen to form a second feedstock containing olefins and containing a second content of dienes that is at least 100 wppm and less than 4000 wppm total dienes;
• c) contacting the second feedstock and an olefinic recycle stream with a molecular sieve catalyst in a reaction zone under conditions sufficient to oligomerize the olefins, the oxygenate content in the second feedstock within about 500 wppm of the oxygenate content in the first feedstock, wherein the contacting is such that:
• (i) the olefinic recycle stream and the second feedstock are present in a weight ratio of about 0.1 to about 3.0,
• (ii) the conditions in the reaction zone comprise a WHSV of at least 1.0, based on the olefins contained in the second feedstock, and
• (iii) the reaction zone exhibits a temperature range comprising a difference between a highest temperature and a lowest temperature, wherein the difference is 40° F. (22° C.) or less, thus producing an oligomerization effluent stream;
• and
• d) separating the oligomerization effluent stream into at least the olefinic recycle stream and a hydrocarbon product stream, such that the olefinic recycle stream contains no more than 10 wt % of C10+ non-normal olefins, and such that the hydrocarbon product stream contains from 1 wt % to 30 wt % of C9 non-normal olefins and at least 70 wt % of components boiling at a temperature from about 365° F. to about 495° F. (about 185° C. to about 257° C.).