Properties and Structure of Nanosized Catalyst Systems Based on Molybdenum Sulfides

Abstract

The phase compositions of molybdenum sulfide-based catalysts with various S/Mo ratios which are synthesized ex situ from reverse emulsions of the aqueous solution of ammonium paramolydbate (NH₄)₆Mo₇O₂₄. 4Н₂О in the medium of vacuum residue in the presence of a sulfiding component (sulfur) are studied by chemical thermodynamics and X-ray diffraction. Issues related to the interpretation of the phase composition determining properties of the catalysts are discussed in detail. It is shown that the catalyst predominantly comprising MoS₂ is formed at S/Mo above 2.5 (mol/mol) in the reverse emulsion and the content of carbon-containing components adsorbed on Мо-containing particles grows with an increase in the degree of sulfiding.