Abstract: A method for lightening a petroleum hydrocarbon oil by distillation in which 1 part by weight or less of an organic compound having an active mercapto group therein is added to 100 parts by weight of the petroleum hydrocarbon oil when the petroleum hydrocarbon oil is lightened by a thermal treatment.
Type:
Grant
Filed:
June 22, 1988
Date of Patent:
June 5, 1990
Assignees:
Seibu Oil Co., Ltd., Unique Chemical Consultant, Ltd.