Effect of silicon content on active catalytic phase for hydrocracking of heavy crude oils

Abstract

The silicon composition effect on acidic properties of Ni[sbond]Mo catalysts was investigated for hydrocracking reaction, where an optimal Si and Al ratio is required for the formation of Brønsted acid sites and as well as of Al³⁺ (IV) tetrahedral coordinated sites. The support composition affects the Si[sbond]OH[sbond]Al network, where cations (Al³⁺ or Si⁴⁺) have a coordination number of IV generating higher Brønsted acidity and macro-pores. The supports and fresh catalysts were characterized by atomic absorption, nitrogen physisorption, FT-IR of CO and pyridine adsorption and ²⁷Al MAS NMR.

Keywords:

• heavy crude oils
• hydrocracking
• hydrodeasphalting
• Ni[sbond]Mo catalysts
• SiO₂[sbond]Al₂O₃

Acknowledgments

The authors want to thank Consejo Nacional de Ciencia y Tecnología (CONACyT) for financial support.