Hydrocracking catalyst and method of hydrocracking heavy oil

Abstract

In a process of hydrocracking heavy oil with a catalyst in petroleum refining, asphaltene contained in heavy oil, and impurities including heavy metals such as nickel and vanadium, are efficiently removed with activated carbon, whereby the reduction in catalyst activity or formation of coke by the impurities can be prevented. The invention provides a hydrocracking catalyst comprising activated carbon extrudate as a carrier activated with steam and having a high distribution of pores having pore sizes in the range of 20 to 200 nm.

Description

TECHNICAL FIELD [0001] The present invention relates to a hydrocracking catalyst and to a method of hydrocracking heavy oil by using it. More specifically, it relates to a method wherein in a step of hydrocracking heavy oil with a catalyst in petroleum refining, asphaltene and impurities including metals such as nickel and vanadium contained in heavy oil are removed with activated carbon so that the reduction in catalyst activity or formation of coke by the impurities is prevented. PRIOR ARTS [0002] A method of treating heavy oil with a catalyst includes fluid catalytic cracking (FCC), hydrocracking, etc. In fluid catalytic cracking, raw oil is fluidized together with a silica alumina catalyst or a zeolite catalyst, and pyrolyzed to produce gasoline mainly. The catalyst on which coke formed and accumulated in the cracking reaction is recycled and reused after the coke is burned in a regenerating tower. [0003] In hydrocracking, heavy oil is hydrocracked with an alumina supported cata...

AI Technical Summary

Benefits of technology

[0015] In the hydrocracking process, an alumina supported catalyst is usually used, and pores are designed to have a relatively large size in order to reduce the clogging of catalyst pores with accumulated nickel and vanadium, but as described by Speight, J. G. in The Chemistry and Technology of Petroleum, Marcel Dekker (1980), acidic sites of the original alumina carrier are effective in hydrocracking activity, but are poisoned by a basic compound contained in heavy oil. Activated carbon has less acidic sites than in the alumina catalyst, and metal oxides carried on the activated carbon carrier can be easily activated.

[0036] Further, the used activated carbon catalyst having nickel and vanadium accumulated thereon can be subjected to burning treatment to recover nickel and vanadium easily.

Problems solved by technology

Because a catalyst is used in fluid catalytic cracking or hydrocracking, the content of nickel and vanadium and the content of residual carbon in heavy oil as a raw oil are limited.

In a regeneration tower, the catalyst is regenerated by burning the coke, but when the amount of accumulated coke is large, the temperature in the regeneration tower is increased to deteriorate the catalyst.

Nickel and particularly vanadium destroy the crystalline structure of zeolite to deteriorate the activity.

The process of removing asphaltene and impurities such as nickel and vanadium with a solvent is a method of merely separating asphaltene, and thus asphaltene in the raw oil is separated as it is, and therefore, as the raw oil becomes heavy, the amount of asphaltene after separation is increased to make use thereof problematic.

As described by Godfried M. K. Abotsi and Alan W. Scanroni in Fuel Processing Technology, 22, pp 107-133 (1989), alumina is problematic in that a metal oxide carried on the carrier is hardly reduced to form an active metal species.

Images