ASPHALTENE CRACKING IN CATALYTIC HYDROTREATING OF HEAVY OIL.

The question how and why asphaltenes are converted or cracked to oils during the Asphaltenic Bottom Cracking Process has arisen and remained unknown. In a previous investigation on the properties of feedstocks and the whole product oils, demetallation and desulfurization were supposed to be two main reactions which are closely related to asphaltene cracking and the decrease and shift of distribution in molecular weight of whole oil by gel permeation chromatography was observed during the asphaltenes cracking reaction. In this work, characteristic analyses of the asphaltenes before and after the reaction were carried out with respect to demetallation and desulfurization from asphaltenes, decrease of molecular weight and changes in the sizes or other structural properties of asphaltenes. This work aims to show that the differences of asphaltene properties between feedstock and product oil can clarify the conversion of asphaltenes to oil.