Catalytic aquathermolysis of super-heavy oil: Cleavage of CS bonds and separation of light organosulfurs

In this work, we developed an advanced bifunctional catalyst with both catalytic center and hydrogen donor to catalyze the aquathermolysis of the super-heavy oil from Shengli oil field. For efficiently separating the organosulfurs, we employed the PdCl2/silica gel ligand exchange chromatography (LEC) to obtain the critical organosulfurs, including polycyclic aromatic heterocycles (PAH), polycyclic aromatic sulfur heterocycles (PASH) and polar sulfur compounds (PSC), before and after aquathermolysis. GC-MS characterizations of the separated organosulfurs show that the nonconjugated CS bonds of high molecular weight compounds were cleaved to reduce the viscosity, while the conjugated CS bonds were stable under the catalytic aquathermolysis condition. Our work may provide a valuable insight on the conversion of organosulfurs in super-heavy oil for developing more efficient catalysts for aquathermolysis.