Aquathermolysis of Ashalcha Heavy Crude Oil Using an Oil-Soluble Catalyst and a Hydrogen Donor: A Kinetic Study

Abstract

Over the last few years, the use of catalysts and solvents to increase the production of active hydrogen has enhanced the aquathermolysis of heavy crude oils. However, none kinetic model has been reported for the combined system. In this work, a kinetic model for the aquathermolysis of Ashalcha heavy oil using Ni-stearate and decalin as hydrogen donor was developed. Based on the obtained kinetic parameters, SARA fractions mainly suffered forward (in a higher degree) and backward reactions from asphaltenes to resins to aromatics. The transformation of heavy fractions and aromatics is raised with the synergic use of decalin and Ni-stearate, favoring the generation of light hydrocarbons, especially saturates. Moreover, the combined use of catalyst and hydrogen donor inhibits the cracking of asphaltenes and resins to produce gas, as well as the agglomeration of aromatics to resins. The sensitivity and statistical analyses verified that the estimated kinetic parameters are the optimal and the optimization is appropriately applied. The low average absolute error values ((5 %) obtained using the developed kinetic model confirm the precise prediction for all SARA and gas fractions employed the reaction scheme.