Hydrogenation of residual oil using an ore derived water soluble ammonium molybdate catalyst

Abstract

Hydrogenation of residual oil, though attractive, has been expensive due to hydrogen requirements, high pressure equipment, and high cost of a generally used cobalt-molybdenum supported catalyst. In this study hydrogenation of atmospheric residual oil (260 °C +) with API gravity of 16 (20 °C) and viscosity of 252 × 10 −3 Pa s (30 °C) is carried out in an internally stirred autoclave in the presence of a dispersed water soluble unsupported ammonium molybdate catalyst prepared from a molybdenum ore. This provides an effective economic alternative to the use of expensive supported commercial catalysts for the hydrogenation of residual oil. The most suitable hydrogenation experimental conditions for the hydrogenation of residual oil were found to be 0.216% molybdenum based on residual oil, 13.8 MPa pressure, 405 °C reactor temperature, and 30 min reaction time. Under these conditions, API gravity of the product oil increased to 23 with a decrease in viscosity to 16.6 × 10 −3 Pa s. An ASTM distillation of the hydrogenated residual product gave 34% liquid boiling below 235 °C.