Core-shell catalysts with CoMoS phase embedded in clay nanotubes for dibenzothiophene hydrodesulfurization

Abstract Nanoarchitectural strategy for design of highly active catalysts with CoMoS encased in 50-nm diameter aluminosilicate tubes (halloysite nanoclay) serving as an abundantly available natural support was proposed. This encapsulation conception implies the protection of active metal sulfides from aggregation, coking and leaching. Synthesized nanocatalytic system was investigated by TEM, XPS, N2 adsorption, hydrogen temperature programmed reduction and desorption of ammonia techniques. Using of Mo-heteropolyacid anionic precursor complex (ca. 10 wt%) possess selective loading of molybdenum oxide into 15-nm diameter inner cavity of the nanotubes (covered with positively charged alumina) by an electrostatic attraction. Subsequent sulfidation results in formation of CoMoS particulate core inside the aluminosilicate shell. These tubular nanoreactors were pelletized using alumina binder to produce a mechanically strong mesoporous catalyst efficient for hydrotreatment of diesel petroleum fraction to clean fuels.