Patent ID: 8119851

Claim:
A process for making a base oil, comprising: a. selecting an olefin feed from a Fischer-Tropsch condensate; b. oligomerizing the olefin feed in an ionic liquid oligomerization zone comprising an acidic ionic liquid catalyst comprising 1-butyl-pyridinium chloroaluminate and HCl as an additive at a set of oligomerization conditions to form an oligomer; c. adding isoparaffin into the oligomerization zone during the oligomerization reaction; and d. adjusting the added amount of isoparaffin to obtain an alkylated oligomeric product having: i. a kinematic viscosity at 100° C. of 6.9 mm2/s or greater, ii. a VI of at least 134, and iii. a Bromine Number of less than 3.