Patent ID: 8431012

Claim:
A heavy hydrocarbon composition derived from a Fischer-Tropsch synthesis process useful as a heavy lubricant oil base stock, the composition having been dehazed by cold filtration using filter media having pores from 0.2 to 5 microns, the cold filtered composition further characterized by at least greater than 50 wt % iso-paraffinic molecules; a distribution of molecules wherein at least 75 wt % of the molecules have a carbon number greater than C 25 ; 10wt % of the total base oil boiling above 537° C.(1000° F.); a kinematic viscosity at 100° C. of at least 8 cSt; and a haze disappearance temperature of 20°C. (68°F.) or less, the cold filtration having been conducted at a temperature of at least about 5°C. below the haze disappearance temperature.