Oxidative propane dehydrogenation using CO2 (CO2‐ODHP) is a potential alternative for propylene synthesis. In this study, bifunctional catalysts (V2O5, ZrO2, Cr2O3, and Ga2O3 doped H‐ZSM‐5) are synthesized through additive manufacturing for CO2‐ODHP. Characterization and correlation between the various characterizations and the catalytic results indicates that the direct 3D printing of metal oxides alongside H‐ZSM‐5 can considerably modify the surface properties and bulk oxide phase dispersion, thus leading to enhanced metal oxide reducibility and exceptional CO2‐ODHP performance. Among the metal monoliths, the mixed oxide sample with 5 wt% Cr, 10 wt% V, 10 wt% Zr, 10 wt% Ga and 65 wt% H‐ZSM‐5 displays the best activity, achieving ≈40% propane conversion, 95% propylene selectivity, and zero benzene/toluene/xylene production. Upon eliminating CO2, the catalyst monoliths all retain their long‐term stability; however, the propane conversions decrease by ≈3% and the propylene selectivities decreased by 5–15%. Nevertheless, all five samples examined here demonstrate exceptional catalytic activities and prolonged stabilities, which are attributed to the even distribution of surface acid sites produced by direct printing of the oxide and zeolite components. Overall, this study presents a novel way of manufacturing bifunctional structured catalysts that exhibit exceptional ODHP performance.

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The effects of some process conditions on isomer distributions during the partial hydrogenation of trilinolein with a copper type catalyst were studied. Modest effects on diene isomer distributions were noted by changes in temperature. Pressure and catalyst concentration, however, had little or no effect on diene isomer distributions over the range studied. Distribution of monoene isomers appeared to be insensitive to process conditions and extent of the reaction and suggests an equilibrium reaction. Very small amounts of saturates, if any, were formed during the reactions. The data support a conjugation then hydrogenation mechanism for hydrogenation of glyceryl dienoates with copper catalysts.

We have compared a nickel with a copper catalyst in the formation of some geometrical and positional isomers during the partial hydrogenation of trilinolein. The copper catalyst was found to produce fewer diene isomers than the nickel catalyst at a comparable iodine value. The copper catalyst produced more monoene isomers however, than did the nickel, particularly trans monoenes. The distribution of the monoene isomers appeared to obey an equilibrium relationship with each other, independent of both iodine value and reaction conditions. We have presented additional evidence to postulate that copper catalysts hydrogenate polyenoi c acids by first conjugating the acids. The selectivity of copper catalysts for triene over diene is probably due to the greater ease of conjugation of the triene.