Patent ID: 7241375

Claim:
A heavy hydrocarbon composition comprising at least 95 wt % paraffin molecules, of which at least 90 wt % are isoparaffins, containing hydrocarbon molecules having consecutive numbers of carbon atoms, is a liquid at 100° C., at which temperature its kinematic viscosity, as measured by ASTM D-445, is above 8 cSt, has an initial boiling point of least 850° F. (454° C.) and an end boiling point of at least 1000° F. (538° C.), wherein the branching index (BI), as measured by the percentage of methyl hydrogens, and the branching proximity (CH 2 >4), as measured by the percentage of recurring methylene carbons which are four or more carbon atoms removed from an end group or branch, of said isoparaffinic hydrocarbon molecules, are such that: (a) BI−0.5(CH 2 >4)<15; and (b) BI+0.85(CH 2 >4)<45; as measured over the heavy hydrocarbon composition as a whole.