A mechanistic model on catalyst deactivation by coke formation in a continuous stirred tank reactor (CSTR) has been developed the paper. Catalyst was treated as surface reaction. Four reaction mechanisms representing through different routes were proposed. The evolved system of ordinary differential equations (ODEs) solved numerically using MATLAB. This approach validated applying it to skeleta...

Activation of a catalyst [IrCl(COD)(IMes)] (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; COD = cyclooctadiene)] for signal amplification by reversible exchange (SABRE) was monitored by in situ hyperpolarized proton NMR at 9.4 T. During the catalyst-activation process, the COD moiety undergoes hydrogenation that leads to its complete removal from the Ir complex. A transient hydride i...

Active sites are created on the surface of a Li/MgO catalyst used for the selective oxidation of methane by the gradual loss of carbondioxide from surface carbonate species in the presence of oxygen. Decomposition of the carbonat~ species in the absence of oxygen is detrimental to the activity of the cataIy~t. The active sites'created are not stable but disappear either as a result of reaction ...

Mesoporous alumina catalysts that incorporate nickel (Ni-Alumina) with different Ni/Al molar ratios of 1:2, 1:5 and 1:10 were synthesized by a one-step sol–gel method using lauric acid as a template. The prepared Ni-Alumina catalysts showed a relatively high surface area with a narrow pore size distribution after calcination at 700 ◦C; these effects were independent of the Ni/Al molar ratio. Al...

An integrated approach to the modelling of chemical reactors, particularly catalytic ones is presented. The modelling approach starts from quantum-chemical calculations, mechanistic hypothesis, derivation of kinetic expressions in order to achieve an appropriate kinetic model. The model parameters are determined by regression analysis and the complex behaviour of fixed bed reactors, including c...

The performance of fixed and fluidized bed reactors in the steam reforming biomass fast pyrolysis volatiles was compared, with especial attention paying to differences observed catalysts deactivation. experiments were carried out continuous regime a bench scale unit provided conical spouted for step. They on Ni-Ca/Al2O3 commercial catalyst under optimum conditions determined previous studies, i...

Vapour phase hydrogenation of nitrobenzene is carried out over metal (Pt, Pd, Ru, Ni) supported on hydroxyapatite (HAP) catalysts at atmospheric pressure and low temperatures ranging from 225–350 °C. The time-on-stream analysis reveals that 2 wt.%Pd/HAP is quite stable up to 6 h of continuous operation and is found to be an efficient catalyst. The other metal catalysts suffer deactivation, whic...