Kinetic model for Boca de Jaruco heavy crude oil catalytic aquathermolysis using NiSO4 catalyst

Abstract

In recent times, water-soluble catalysts have exhibited good results for reducing the viscosity during the catalytic aquathermolysis of heavy oils, being a good alternative to enhance steam injection technologies. Nonetheless, currently there is no kinetic model with these types of catalysts for such reaction. This work reports the development of a kinetic model based on SARA fractions for the aquathermolysis of Boca de Jaruco heavy oil using NiSO4 as water-soluble catalyst. Asphaltenes conversion into smaller fractions prevails as the easiest reaction at catalytic aquathermolysis conditions followed by the condensation reactions of SARA fractions (saturates - aromatics - resins - asphaltenes). This complex fraction is also the main producer of gases since their generation from other fractions is less likely to be carried out. The kinetic parameters were correctly estimated and their optimal values were confirmed based on sensitivity and statistical analyses. The accuracy of experimental data prediction was demonstrated with 6.9 % of average absolute error. It was concluded that the water-soluble catalyst promotes the conversion of asphaltenes and hinders the over-cracking reactions of light fractions.