Aquathemolysis Reaction of Heavy Oil by a MoWNiC Nanocrystalline Catalyst Produced by Mechanical Alloying

Abstract

MoWC-NiC-WC was produced by mechanical alloying at the following grinding times: 0, 40, 80, 120, 160, 200 and 240 h. XRD results indicated that by increasing the milling time from 0 to 240 h, the nanostructured carbide phases were synthesized with a crystal size ranging from 125.6 to 10.1 nm. The performance of the nano-catalysts in the heavy oil before and after the reaction was analyzed by Fourier transform infrared spectroscopy (FTIR), Viscosimetry, SARA method analysis by Thin-layer chromatography-flame ionization detection (TLC-FID), elemental (EL) analysis, and gas chromatography/mass spectroscopy (GC/MS). As the milling time increased, the ratio of the viscosity reduction of the heavy oil increased from 80.4 to 97.1 % by using the catalyst milled for 240 h. In addition, the results showed that some reactions were observed during the aquathermolysis: pyrolysis, depolymerization, hydrogenation, isomerization, ring opening, desulphurization, etc. It was also found that the catalysts at short milling times caused more changes in the resin, saturated hydrocarbon, and oxygen-containing groups, whereas the 240 h catalyst led to more changes in the asphaltene, aromatic hydrocarbon, and sulfur-containing groups.