A kinetic model of a fixed bed tubular reactor incorporating catalyst deactivation was developed for the ISOMAX unit of Arak refinery. The kinetic parameters for the hydrocracking reactions over the commercial catalyst were determined using initial activity plant data i.e. when the catalyst is fresh. Catalyst deactivation was then taken into account by means of deactivation function based on pl...

Ag films were grown by pulsed laser deposition on insulating SiO2 and mica substrates and exhibited a morphological progression beginning with nucleation of 3D islands and culminating in a continuous, electrically conducting film. The rate of advancement through this progression with increasing pulse frequency was studied with experiments and with Kinetic Monte Carlo simulations. Experiments at...

A rapid, sensitive and versatile kinetic method is presented for the simultaneous spectrophotometric determination of iodide and iodate by partial least-squares regression (PLS) using original and derivate data named as absorbance and rate data. The method is based on the catalytic effect of the cited anions on the reaction rate between Ce(IV) and As(III) in 2 mol l?1 sulfuric acid medium. The ...

a theoretical study of the kinetic and mechanism of 3-aug-cope rearrangement in gas phase was performed usingdet methods at b3lyp levels of theory with 6-3114ig(d,p) bass set at 298.i5k. equilibrium moleculargeometries and harmonic vibrational frequencies of the reactant, transition state did product were calculated. then,rate constant and activation thermodynamics parameters were calculated an...

Problem statement: Nitrification by Moving Bed Biofilm Reactor (MBBR) involves physical, chemical and biological processes to remove toxic ammonia for aquaculture that are governed by a variety of parameters, like substrate and dissolved oxygen concentrations, organic matters, temperature, pH, alkalinity and turbulence level, which impact negatively or positively on nitrification kinetics. App...

in present study, the kinetic parameters of purified trypsin from pyloric caeca of common kilka (c.cultriventris caspia) were measured using the amidolytic (bapna) and esterolytic (tame) substrates. the results of the kinetic comparison between bapna and tame substrates showed that kinetic parameters including maximum velocity (vmax), catalytic constant (kcat) and catalytic efficiency (kcat/km)...

in this study, the stability of trinitroglycerin (tng) in polyethylene (peg) 400 was investigated according to arrhenius approach. the reaction rate constant (k) for the thermal disintegration of tng in peg 400 at various temperatures was counted based on the percents of remaining tng at different intervals of time at a specific temperature. the results showed that “k” at 40, 50, 60, 70, 80 and...

the solutions of mathematical models for the estimation of the kinetic, and biokinetic parameters of naphthalene, anthracene and pyrene during degradation in surface and subsurface soils are presented in this work. the models were developed using the twin concepts of rate-determining step and steady-state approximation method. they described the biodegradation of single and a mixture of polycy...