Patent ID: 8367883

Claim:
A method of manufacturing naphtha, comprising: fractionating synthetic oil, which is obtained by Fisher-Tropsch synthesis, in a fractionator to separate the synthetic oil into a naphtha fraction as raw naphtha containing 10% by mass or more of an olefin and 5% by mass or more of an alcohol, and at least one fraction containing a hydrocarbon heavier than the naphtha fraction; and hydrogenating the naphtha fraction by bringing the naphtha fraction into contact with a hydrogenating catalyst in a hydro-refining apparatus to remove the alcohol and the olefin, thereby producing a hydrogenated naphtha fraction containing substantially only a paraffin component, wherein 20% to 80% by volume of the produced hydrogenated naphtha fraction with respect to the raw naphtha is recycled to the raw naphtha to hydrogenate the naphtha fraction whereby heat generation due to hydrogenation of the olefin and hydrogenation of the alcohol is suppressed.