Deoxygenation of stearic acid with a novel Ni(CO)‐MoS₂/Fe₃S₄ catalyst

Abstract

Magnetically recyclable Ni(Co)-promoted MoS 2 catalysts with greigite (G) core were synthesized and their activity and selectivity in hydrodeoxygenation of stearic acid were investigated. The activity of the catalysts tested at 320 8C and H 2 initial pressure of 3.5 MPa could be ranked as NiMo/G > CoMo/G > Mo/G. Two main products were detected, C18 (through HDO pathway) and C17 hydrocarbons (through DCO pathway). HDO was the dominant pathway for all of the catalysts. As for the C18/C17 ratio, the catalysts were found to be in the order: Mo/G > CoMo/G % NiMo/G. The Paraffin/Olefin ratio was over 1 for all of the catalysts with NiMo/G showing the highest ratio. Stearic acid was found to have an inhibiting effect on the adsorption of intermediates over the active sites. Moreover, the concentrations of intermediates decreased at high conversions of stearic acid. The formation of the intermediate aldehyde is through C-O hydrogenolysis of the fatty acid following the protonation, dehydrogenation, and hydride addition steps. The same steps were suggested to be involved in the transformation of the aldehyde to the alcohol. Formation of C n-1 hydrocarbons was found to be via decarbonylation route. The enhancement of the DCO pathway over the promoted catalysts was related to the electron transfer from the promoting atom to an adjacent sulphur atom and reduction in sulphur-metal bond strength.

Production of green diesel from catalytic deoxygenation of chicken fat oil over a series binary metal oxide-supported MWCNTs

“…Ni 10 /MWCNT exhibited the highest CO gaseous (87%), indicating that decarbonylation is the predominantly involved route. 50 Ni edges pose greater C affinity and are susceptible to the Boudouard reaction. 51 Thus, a catalyst containing Ni may partially undergo a Boudouard reaction to form CO.…”

The critical role of solvent polarity in the preparation of tube-like Co–Mo sulfide catalysts for the hydrodeoxygenation of stearic acid

“…This is because the competitive adsorption of SA on the active sites inhibited the alkene hydrogenation reaction. 40,41 The C 36 –e deoxygenation was slower probably because its large molecule size inhibited the contact of the ester functional groups with the active sites and further activation. 42 Thus, the reaction temperature can be increased to degrade the C 36 –e to octadecanol and octadecane, which was further hydrogenated and deoxygenated directly to obtain hydrocarbons.…”

“…This is because the competitive adsorption of SA on the active sites inhibited the alkene hydrogenation reaction. 40,41 The C 36 -e Fig. 7 Effect of the reaction temperature on the conversion of SA over various sulfide catalysts.…”

Surface treated cotton fabric with stain repellent property for the use in aircraft upholstery

“…In step 3, stearic acid was dissolved in acetone and it was allowed to react with the product from step 2, which consist with unreacted OH groups available in TiO 2 sol solution. 41 As stearic acid consists with many hydrocarbon groups it assists to improve the hydrophobicity of the cotton fabric, which indicates as the end product of step 3 in the Scheme 1.…”