Aquathermolysis of high-viscosity oil terrigenic sediments in the presence of iron oxide (II, III)

Abstract

Nowadays, it is especially important and relevant to improve the efficiency of existing methods of enhanced oil recovery, in particular, thermal methods using water steam. The use of catalysis at the stage of development of unconventional hydrocarbon fields, namely super-viscous and bituminous oils, will allow solving this problem. This work is devoted to the study of the transformation of heavy oil from the Ashalchinskoye field in the process of catalytic aquathermolysis. The oil samples were extracts from sandstone, which was subjected to thermal steam treatment in a high-pressure reactor at temperatures of 200 and 250C for 24 h. Nanosized iron (II, III) oxide in complex with a hydrogen donor was used as a catalytic composition. According to the results of SARA-analysis, it was found that at a temperature of 200C, iron oxide does not show its catalytic properties, and there is no noticeable improvement in the composition of heavy oil. The destruction of resins and asphaltenes is observed after thermocatalytic treatment at 250C. This leads to the enrichment of oil with lighter hydrocarbons, which is confirmed by GC-MS data of the saturated fraction of oil. All this provides a significant decrease in the viscosity of heavy oil compared to the non-catalytic process from 1140 cP to 37 cP The formation of coke-like substances adsorbed on sandstone as a result of thermocatalytic action at 250C was revealed by the results of TG-DSC.