The stability of palladium supported on ceria (Pd/CeO2) was studied during liquid flow transfer hydrogenation using primary and secondary alcohols as hydrogen donors. For primary alcohols, the ceria support was reduced to cerium hydroxy carbonate within 14 h and was a contributing factor toward catalyst deactivation. For secondary alcohols, cerium hydroxy carbonate was not observed during the s...

The refining industry is currently undergoing its most serious challenge in recent times, since cleaner fuels are gradually introduced in many markets. Middle East countries still have less history than Europe, Japan or the USA when it comes to clean fuels, but the trend is there, which will eventually increase the demand for hydroprocessing catalysts. On the other hand, more sophisticated cata...

Deactivation of heterogeneous catalysts is a ubiquitous problem that causes loss of catalytic rate with time. This review on deactivation and regeneration of heterogeneous catalysts classifies deactivation by type (chemical, thermal, and mechanical) and by mechanism (poisoning, fouling, thermal degradation, vapor formation, vapor-solid and solid-solid reactions, and attrition/crushing). The key...

Rh(III)-TsDPEN, an immobilized analog of the well-known [Cp*Rh(bpy)(H(2)O)](2+) was evaluated as a heterogeneous, recyclable regeneration catalyst for reduced oxidoreductase cofactors [NAD(P)H]. Repeated use of this catalyst was established and the catalytic properties were initially investigated. Apparently, Rh(III)-TsDPEN is prone to severe diffusion limitations, necessitating further develop...

The samples of spent chlorinated Pt/Al2O3 catalysts that were used in the isomerization process were decoked at elevated temperatures under airflow and different oxygen concentrations. The surface of the catalyst was characterized by thermal gravimetric analysis, differential scanning calorimetry, Brunauer-Emmett-Teller analysis, attenuated total reflection fast Fourier in...

Ex-situ catalytic pyrolysis of pure glycerol to bio-aromatics over an un-modified H-ZSM-5 zeolite. • The conversion aromatics (BTX) with zeolite was investigated. An ex-situ approach used a separate and upgrading unit. A BTX peak carbon yield 28.1 ± 0.2% obtained. Catalyst performance for 5 reaction/regeneration cycles determined. Irreversible catalyst deactivation observed due dealumination th...

Diesel oxidation catalysts (DOC) were investigated for activity, NO conversion stability, and sulfur poisoning/regeneration on Pd/Al2O3, Pt/Al2O3, Pd-Pt/Al2O3 catalysts. The Pd/Al2O3 catalyst was more active CO hydrocarbon (C3H6 C3H8) oxidation, while the Pt/Al2O3 efficiently oxidized NO. formation of a Pd-Pt alloy in maintained Pd reduced phase, resulting superior activity this CO, C3H6, compa...