Optimization of heavy crude oil recovery using oil-soluble catalyst precursor under electromagnetic heating

• The effect of using oil-soluble catalysts on improving the quality of heavy oil under electromagnetic heating was investigated. • The total heavy compounds (asphaltene and resin) decreased by 42.4 after 9 min of radiation time. • A viscosity reduction of 60% was achieved utilizing oil soluble catalyst. • GC–MS showed a decrease in the content of heavy components (n-C26-C32) two times after 6 min. In order to improve the heavy oil quality, the electromagnetic (EM) heating method with the addition of metal catalysts has been considered. Oil-soluble catalyst precursors, which consist of a ligand and a metal, prevent their clumping and precipitation by dispersing nanoparticles in oil. Unfortunately, no research was found to investigate the effect of adding this type of catalyst on increasing the efficiency of EM heating and optimizing the recovery of heavy oil. The aim of this paper was to propose nickel-adipic (NOSC) as an oil-soluble catalyst precursor to increase the efficiency of EM heating. A set of 2.45 GHz industrial magnetrons was used as the microwave radiation source with the addition of 1 wt% NOSC (containing 0.39 % Ni) at time intervals of 3, 6 and 9 min. At 9 min, asphaltene and resin content decreased by 21.91 % and 40.07 %, and saturate and aromatic content increased by 11.13 % and 41.3 %, respectively. In addition, the viscosity also showed a decrease of about 60 %. Elemental analysis showed 11 %, 13 % and 20 % reduction of sulfur after 3, 6 and 9 min, respectively. According to the results of GC–MS, the content of n-C 26 –C 32 compared to the control sample (ACO) was reduced by 2 times in 6 min. In addition, observing the increase in the content of naphthalenes and light alkylbenzenes in aromatic compounds was a proof of the effectiveness of the NOSC catalytic system in heavy oil upgrading. This paper presents a promising approach to enhance the performance of EM heating in heavy crude oil recovery.