Cyclohexene Hydroconversion Using Monometallic and Bimetallic Catalysts Supported on γ‐Alumina

Abstract

The hydroconversion of cyclohexene (CHE) using monometallic catalysts containing 0.35wt% of Pt, Pd, Ir or Re on a γ‐alumina support, as well as bimetallic catalysts containing combinations of 0.35wt% Pt with 0.35wt% of either Pd, Ir or Re on γ‐alumina, were investigated in a plug flow‐type fixed‐bed reactor. The Cyclohexene (CHE) feed was injected continuously with a rate of 8.33 × 10−3mole h−1 on 0.2 g of catalyst using a simultaneous hydrogen gas flow of 20 cm3 min−1 throughout a broad reaction temperature range of 50–400 °C. The dispersion of the metals in the catalysts was determined via H2 or CO chemisorption. The activities of the monometallic catalysts were found to be in the order: Pd > Pt > Ir > Re, whereas those of the bimetallic catalysts were in the order: PtPd > PtIr > PtRe. Cyclohexene hydrogenation and dehydrogenation reactions using the current mono‐ and bimetallic catalysts were kinetically investigated applying the absolute reaction rate theory, whereby reaction rate constant, activation energy, enthalpy and entropy of activation were computed to explain surface variations on these catalysts.

Competitive Hydrogenation between Linear Alkenes and Aromatics on Close-Packed Late Transition Metal Surfaces

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A Non‐Phosgene Route Synthesis of Carbamate in Continuous Fixed Bed Reactor

“…Great interest has developed in recent decades in the palladium-based bimetallic catalysts. [21][22][23] The incorpo- Fig. 3.…”

C-Heterogenized Re Nanoparticles as Effective Catalysts for the Reduction of 4-Nitrophenol and Oxidation of 1-Phenylethanol

“…Rhenium is a very promising element to be used as a versatile catalyst. Apart from bare metal, rhenium nanoparticles (Re NPs) can serve as catalysts when supported on polymers [6], in DNA scaffold [7], carbon [8], γ-Al 2 O 3 [9], etc. For example, Ni et al successfully prepared supported rhenium catalysts by the microwave-assisted thermolytic method, and the as-prepared catalysts showed good catalytic properties in the hydrogenation of cinnamaldehyde [10].…”