GB787538A - Improvements in or relating to the manufacture of gasolene - Google Patents

Abstract

Gasoline of high octane rating is obtained by subjecting to a catalyzed reforming reaction in the presence of hydrogen, a fresh gasoline fraction together with a recycle fraction obtained in the process, separating off the normally gaseous products and submitting the normally liquid products to an extraction treatment and separating the products into an extract rich in aromatic hydrocarbons and into a raffinate poor in aromatic hydrocarbons and subjecting the raffinate to fractional distillation to obtain a low boiling fraction comprising all of the components boiling below hexane and a higher boiling fraction which is returned to the initial reforming step as the recycle fraction, and commingling at least a portion of the low boiling raffinate fraction with said extract to form high octane rating gasoline. In a preferred form of operation, the lower boiling fraction is commingled with the aromatic-rich hydrocarbon phase by being introduced as a reflux stream to the extraction zone to improve simultaneously the separation effected in this zone and to blend the low boiling fraction with the extracted hydrocarbon material. The reforming is preferably effected at a temperature of 316 DEG to 538 DEG C. and a pressure of 13.6 to 68 atmospheres in the presence of hydrogen at a mol. ratio of 0.5 to 20 mols. of hydrogen per mol. of hydrocarbon in contact with a reforming catalyst comprising alumina, platinum in a weight per cent of from 0.01 to 1 and 0.1 to 3.0 per cent of combined halogen. The catalyst may consist of palladium, nickel, cobalt, iron, manganese, chromium, molybdenum, or tungsten either alone or in combination with Group VI and Group VIII metals, these metals may also be used as sulphides, oxides or phosphates and on a carrier such as bauxite, pumice, kieselguhr, diatomaceous earth, montmorillonite or clay, or synthetically prepared alumina, silica, magnesia, zirconia, boria or mixtures such as silica-alumina, silica-magnesia, silica-aluminina-zirconia, with or without an activating agent such as halogen, phosphate or sulphate. The solvent may be an alcohol, a glycol, an aldehyde, glycerine or phenol or ammonia. Specified glycols are diethylene glycol, triethylene glycol, dipropylene glycol and tripropylene glycol. Specification 657,565, [Group IV (a)], is referred to.ALSO:Gasoline of high octane rating is obtained by subjecting to a catalysed reforming reaction in the presence of hydrogen, a fresh gasoline fraction together with a recycle fraction obtained in the process, separating off the normally gaseous products and submitting the normally liquid products to an extraction treatment and separating the products into an extract rich in aromatic hydrocarbons and into a raffinate poor in aromatic hydrocarbons and subjecting the raffinate to fractional distillation to obtain a low boiling fraction comprising all of the components boiling below hexane and a higher boiling fraction which is returned to the initial reforming step as the recycle fraction, and commingling at least a portion of the low boiling raffinate fraction with said extract to form high octane rating gasoline. In a preferred form of operation the lower boiling fraction is commingled with the aromatic-rich hydrocarbon phase by being introduced as a reflux stream to the extraction zone to improve simultaneously the separation effected in this zone and to blend the low boiling fraction with the extracted hydrocarbon material. The reforming is preferably effected at a temperature of 316 DEG to 538 DEG C. and a pressure of 13.6 to 68 atmospheres in the presence of hydrogen at a mol. ratio of 0.5 to 20 mols. of hydrogen per mol. of hydrocarbon in contact with a reforming catalyst comprising alumina, platinum in a weight per cent of from 0.01 to 1 and 0.1 to 3 per cent of combined halogen. The catalyst may consist of palladium, nickel, cobalt, iron, manganese, chromium, molybdenum or tungsten either alone or in combination with Group VI and Group VIII metals, these metals may also be used as sulphides, oxides or phosphates and on a carrier such as bauxite, pumice, kieselguhr, diatomaceous earth, montmorillonite or clay, or synthetically prepared alumina, silica, magnesia, zirconia, boria or mixtures such as silica-alumina, silica - magnesia, silica - alumina - zirconia, with or without an activating agent such as halogen, phosphate or sulphate. The solvent may be an alcohol, a glycol, an aldehyde, glycerine or phenol or ammonia. Specified glycols are diethylene glycol, triethylene glycol, dipropylene glycol and tripropylene glycol. Specification 657,565 is referred to.