UNLEADED GASOLINE AND PRODUCTION OF HYDROGENATED LOW-MOLECULAR-WEIGHT ISOBUTYLENE POLYMER AS ITS BASE

摘要

PURPOSE:To prepare a hydrogenated low-mol.-wt. isobutylene polymer usable as a base of high-octane unleaded gasoline by hydrogenating a specified low- mol.-wt. isobutylene polymer under specified conditions (pretreatment) and then hydrogenating a mixture of the hydrogenated product and the starting material at a specified mixing ratio (main reaction). CONSTITUTION:As a pretreatment, a low-mol.-wt. isobutylene polymer comprising 55-72vol.% isobutylene dimer and 25-40vol.% isobutylene trimer is hydrogenated in the presence of a hydrodesulfurizing catalyst at a recycle ratio of 80-100%, under a hydrogen pressure of 45-65kg/cm2, at a temp. ranging from ordinary temp. to 180 deg.C, at a liq. space velocity of 0.1-12hr-1 to form a hydrogenated product. Then, as a main reaction, a mixture of the starting material and the hydrogenated product (3/97 to 40/60) is hydrogenated under a hydrogen pressure of 25-35kg/cm2, at 150-350 deg.C, at a liq. space velocity of 1-12hr-1, up to a conversion of 80-90%. The hydrogenated low-mol.-wt. isobutylene polymer thus obtd. is usable as a base for high-octane unleaded gasoline superior to prior ones in quality.