The present study investigates the decomposition of ammonia (NH3) over Ni and Ru catalysts using a kinetic model based on a reaction mechanism consisting of kinetically important elementary steps. Experimental results obtained over a wide range of reaction conditions were reproduced by the model. Recombinative N2 desorption was the rate-limiting step on the Ru catalyst; whereas, the overall rat...

Quantum chemical molecular dynamics simulations of graphene nucleation on the Ni(111) surface show that graphene creates its own step-edge as it forms. This "step-edge self-assembly" is driven by the formation of thermodynamically favorable Ni-C σ-bonds at the graphene edge. This dynamic aspect of the Ni(111) catalyst is in contrast to the commonly accepted view that graphene nucleates on a pre...

The kinetics and reaction network of hydrodemetallation (HDM) reactions and the pattern of metal deposition have been investigated using a model residuum oil, consisting of nickel porphyrins (Nietioporphyrin (Ni-EP), Ni-tetraphenylporphyrin (Ni-TPP), and Nitetra(3-methylphenyl)porphyrin (Ni-T3MPP)) dissolved in a clean (N and S free) mineral oil. Reactions were carried out over a commercial CoO...

The influence of the amount of alumina binders on the catalytic performance of Ni/HZSM-5 for hydrodeoxygenation of cyclohexanone was investigated in a fixed-bed reactor. N2 sorption, X-ray diffraction, H2-chemisorption and temperature-programmed desorption of ammonia were used to characterize the catalysts. It can be observed that the Ni/HZSM-5 catalyst bound with 30 wt.% alumina binder exhibit...

Cross-couplings of alkyl halides and organometallic species based on single electron transfer using Ni and Fe catalyst systems have been studied extensively, and separately, for decades. Here we demonstrate the first couplings of redox-active esters (both isolated and derived in situ from carboxylic acids) with organozinc and organomagnesium species using an Fe-based catalyst system originally ...

The applicability of electro-Fenton technology to remediation of wastewater contaminated by several organic pollutants such as dyes and polycyclic aromatic hydrocarbons has been evaluated using iron-enriched zeolite as heterogeneous catalyst. The electro-Fenton technology is an advanced oxidation process that is efficient for the degradation of organic pollutants, but it suffers from the high o...

The adsorption properties of CO and H2 on iron-based catalyst with addition of Zr and Ni were investigated using temperature programmed desorption process. It was found that on the carburized iron-based catalysts, molecular state and dissociative state CO existed together. The addition of Zr was preferential for the molecular state adsorption of CO on iron-based catalyst and the presence of Ni ...

The Zeolite Y as a support was modified by the incorporating of Fe and TiO2 in one single step using impregnation method. The synergistic effects between those components enhance the catalytic activity for the degradation of amaranth dye under ultrasonic irradiation with output power of 50 W and 40 kHz frequency. Different characterization techniques were used to elucidate the physical and chem...

Pt-loaded β-type zeolite catalysts with constant Pt content (0.11 wt.%) and similar pore structure were prepared using a water-in-oil (w/o) microemulsion. The effect of Pt particle synthesis conditions using microemulsion (a type of Pt complex-forming agents and the molar ratio of complex-forming agent to Pt4+) on loaded Pt particle size was investigated. The Pt particle size of the Pt catalyst...

The simultaneous combination of steady state isotopic transient kinetic analysis (SSITKA) with diffuse reflectance Fourier transform spectroscopy (DRIFTS) and mass spectrometric (MS) analysis was applied to study the oxidative carbonylation of methanol (MeOH) to dimethyl carbonate (DMC) on a CuY zeolite catalyst prepared by incipient-wetness impregnation of commercial zeolite NH(4)-Y. The inter...