Patent ID: 7282139

Claim:
A method for optimizing the operation of a hydrocracker for the production of synthetic diesel and naphtha derived from a Fischer-Tropsch process, the method comprising the steps of: (a) providing a synthetic heavy hydrocarbon feed characterized by a 5% boiling point equal to or greater than 600° F., wherein the synthetic heavy hydrocarbon feed is derived from a Fischer-Tropsch reaction product, the Fischer-Tropsch reaction product being characterized by an α; (b) reacting the synthetic heavy hydrocarbon feed with hydrogen in a hydrocracker under conversion promoting conditions so as to form a hydrocracked effluent comprising a middle distillate and a light distillate; (c) determining a target molar ratio of hydrocarbon molecules exiting the hydrocracker to hydrocarbon molecules entering the hydrocracker, said determination being based on the synthetic heavy hydrocarbon feed α and a desired hydrocracked effluent property; and (d) adjusting at least one hydrocracker conversion promoting condition so as to approach the target molar ratio of hydrocarbon molecules exiting the hydrocracker to hydrocarbon molecules entering the hydrocracker.