Ultra dispersed magnetite as a catalyst for aquathermolysis of heavy oil

Abstract

© SGEM2018. Presently intensification of heavy oil production, particularly by applying various catalytic systems, is very attractive and relevant task for many researchers. Catalysts intensify a destruction process of high molecular compounds such as resins and asphaltenes. Thus, providing irreversible viscosity reduction of nonconventional crude oils. In this regard, investigation of ultra-dispersed catalysts based on transition metals is of current interest. The small particle sizes of catalysts yield a strong activity during aquathermolysis process and are able to penetrate deeply into porous media. In this paper, a synthesis and investigation of spherical iron oxide (magnetite) with particle size of 150 nm are proposed. Further, its efficiency within hydrogen donor during steam treatment of heavy oil is justified. The physical simulation of aquathermolysis process is carried with a heavy crude oil sample from Ashal’cha field of Tatarstan Republic at 250-300°С. The treatment time range in the presence of water with a ratio of 30 wt % was 6 and 24 hours. According to experimental results of X-ray diffraction and electron microscopy, it is revealed that increasing treatment time and temperature brings to formation of various derivative compounds of oxides such as maghemite, pyrite and hematite. Besides the results of SARA-analysis indicate the reduction in asphaltene fraction, which is explained by activity of catalysts directed to destruction of mostly asphaltene compounds. In its turn, the asphaltene reduction influenced the rheology of conversed oil, the viscosity of which reduced by 35 wt %. To continue investigation in this area is attractive in case of applying nanoparticles of iron oxide as a water suspension and compare the efficiency of such a system with already studied ultra-dispersed particles.