Patent ID: 7354507

Claim:
A method for increasing the degree of isomerization of a diesel product comprising: (a) reacting a mixture of hydrogen and carbon monoxide at conversion promoting conditions to form a synthetic hydrocarbon stream, wherein the synthetic hydrocarbon stream comprises primarily C 5+ paraffins; (b) hydrotreating the synthetic hydrocarbon stream under mild hydrotreating conditions; (c) forming a fractionator feedstream comprising the hydrotreated synthetic hydrocarbon stream; (d) separating the fractionator feedstream into at least three fractions including: (i) a light fraction; (ii) an intermediate fraction; and (iii) a heavy fraction; wherein the light fraction has a boiling range with a 5% boiling point of about 300Â° F., wherein the intermediate fraction has a boiling range with a 5% boiling point lower than that of the heavy fraction, and higher than that of the light fraction; (e) passing at least a portion of the heavy fraction to a first hydroconversion zone containing a hydrocracking catalyst; (fe) reacting at least a portion of the heavy fraction from step (d) with hydrogen under hydrocracking promoting conditions in the first hydroconversion zone to form a first hydroconverted effluent; (g) passing at least a portion of the first hydroconverted effluent to a second hydroconversion zone; (h) passing at least a portion of the intermediate fraction to the second hydroconversion zone; and (i) reacting at least a portion of the first hydroconverted effluent and at least a portion of the intermediate fraction with hydrogen in the second hydroconversion zone with a catalyst under conditions suitable to promote hydroisomerization, hydrocracking, dewaxing, or combinations thereof, to form a second hydroconverted effluent, wherein the portion of the intermediate fraction passed to the second hydroconversion zone and the portion of the first hydroconverted effluent passed to the second hydroconversion zone have lost their separate identities.