While possessing the wax content which decreases the wax content hydrocarbon raw materials which contain the hydrocarbon

摘要

PROBLEM TO BE SOLVED: To obtain high-grade middle distillates by bringing a wax-contg. hydrocarbon feed into contact with an alcohol/dilute acid mixed soln. and bringing thus treated feed into contact with specific catalysts at high temp. and pressure to subject the feed to hydrodewaxing and hydrocracking. ;SOLUTION: A solvent mixture is prepd. by mixing a 1-6C alcohol with an aq. dil. acid soln. in an vol. ratio of (10/90)-(90/10). The mixture is brought into contact with a wax-contg. hydrocarbon feed contg. hydrocarbons boiling at 343°C or higher in a vol. ratio of 0.5-5 under the condition that the acid content of the solvent mixture is 1-5vol.%. The treated feed is brought into contact with a crystalline molecular sieve catalyst system having a pore size of 0.5-0.7nm and selected from among metallosilicates and silicoaminophosphates at high temp. and pressure in the presence of hydrogen in a hydrodewaxing zone and then is brought into contact with a catalyst system contg. a group VIB-VIII metal for hydrogenation and zeolite having a pore size of 0.7-1.5nm at high temp. and pressure in a hydrocracking zone, thus giving middle distillates having good low-temp. properties.;COPYRIGHT: (C)1998,JPO