A theoretical study of hydrotreatment of the oxolane molecule without a catalyst and in the presence of a catalyst is performed by numerical DFT/B3LYP methods with 6-31G(d) and LanL2DZ basis sets. The catalyst used in this study is tungsten disulfide (WS2) which is mo­deled by a three anionic vacancy site WS3H3+. Hydrogenolysis of the oxolane molecule under hydrogen pressure is simulated through two sequential stages. The temperature and pressure experimental conditions taken in account in the study were 523, 573, and 623 K under 40 bar. The analysis of variations of diverse system parameters during the process reveals that oxolane undergoes a C—O bonds cleavage at a ring opening at the end of both hydrogenolysis pro­cesses. The first hydrogenolysis process leads to the formation of a butan-1-ol molecule, which then undergoes second hydrogenolysis under the same pressure and temperature conditions. Finally, second hydrogenolysis produces water and butane molecules.