Catalytic conversion of ethanol over supported KCoMoS2 catalysts for synthesis of oxygenated hydrocarbons.

[Display omitted] • KCoMoS 2 catalysts supported on activated carbons were more active in ethanol conversion. • Acidity of catalysts did not have a direct effect on total conversion but it influenced product yields. • Oxygenate yields were higher under a He atmosphere compared to a H 2 atmosphere. • TOF number in ethanol conversion increased with a decrease in dispersion of KCoMoS 2 species. • Resulting oxygenates and their derivatives can have a mixing octane number > 113. The effect of alumina, carbon-coated alumina (CCA), and two commercial activated carbons (ACs) supports on trimetallic KCoMoS 2 catalysts for ethanol conversion was studied. Supports and catalysts were characterized using high-resolution transmission electron (HRTEM) microscopy, UV spectral analysis of pyridine adsorption, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and N 2 physisorption to study their structural properties and morphology. The reactions were carried out under hydrogen and helium reaction atmospheres in a fixed-bed reactor. Catalysts supported on various ACs were found to be more active than those supported on γ-Al 2 O 3 and CCA. The turnover frequency (TOF) in all the studied reactions increased both with an increase in the average length ( L ¯ ) and with a decrease in dispersion (D). Product yields were higher under a helium atmosphere compared to a hydrogen atmosphere. Conversion of ethanol is supposed to occur on MoS 2 -based catalysts with account for the nature of the support and effects of the reaction atmosphere. The influence of catalyst acidity on product distribution and conversion was investigated; acidity was found to have no direct effect on total conversion, yet it influenced product yields. [ABSTRACT FROM AUTHOR]