The run length of cracking furnaces is limited by the formation of coke on the internal skin of the reactor tubes. The reaction mechanism of thermal cracking of hydrocarbons is generally accepted as free-radical chain reactions. On the basis of the plant output data and the insight in the mechanisms for coke formation in pyrolysis reactors, a kinetic model describing the coke formation has been...

A mathematical model for commercial naphtha catalytic reformer of Tehran refinery was developed. This model includes three sequencing fixed beds of Pt/Al2O3 catalyst at the steady state condition using detailed kinetic scheme involving 26 pseudo-components connected by a network of 47 reactions, in the range of C6 to C9 hydrocarbons. The reaction network consisted dehy...

The Biosorption property of S. cerevisiae for chromium uptake was investigated in an immobilized cell bioreactor. Saw dust was utilized as the solid bed in the reactor. Adsorption of S. cerevisiae on saw dust obeys a first order reaction kinetic up to 6 hours. The immobilized biomass particles are porous and exist in the new generation of biological adsorbent. Chromium biosorption was studied i...

The Coats-Redfern method was used to analyze the kinetic characteristics of biomass catalytic pyrolysis, indicating that it can be described by multi-step reactions, rather than as a simple first-order reaction. Friedman model-free calculations were used to describe the starting reaction types and the corresponding initial kinetic parameters. Finally, nonlinear regression of biomass catalytic p...

Mercaptans are commonly present in petroleum products. Their foul odor and highly corrosive nature make them the most undesirable sulfur compounds so they should be removed because of environmental issues. Merox process is used for oxidation of mercaptans to disulfide using air in the presence of alkaline solution and Merox catalyst. In this paper, due to lack of information about the kinet...

Enzyme hydrolysis kinetic model of inulin by inulinase from Kluyveromyces lactis was established. The corresponding Michaelis-Menten equation model constants were found to be related to temperature through the Arrhenius model. The kinetic model was validated by experimental data and also be utilized to predict the hydrolysis reaction rates of the inulin for substrate concentrations ranging betw...

A study of the kinetic analysis of total lead from spent Car battery ash by hydrochloric acidleaching has been examined. The physico-chemical analysis of the ash powder was carried outby the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and X–ray diffraction (XRD).The effects of the acid concentration, temperature and particle size on the rate of battery ashdissolution have been investi...

The parameter estimation using the traditional kinetic modeling of complex reaction systems will give incorrect results if the reaction mechanism contains a loop. In this work, a thermodynamically consistent kinetic model of the anodic electrochemical hydrogen oxidation reaction mechanism of a solid oxide fuel cell (SOFC) is formulated. An iterative algorithm for estimating the reaction rate co...

The surface adsorption of heavy metals in effluents with nanoparticles is today asuitable method for effluents treatment. In the present study, lignocellulose nano-fibers(LCNFs) were used as natural adsorbent for lead adsorption. The aim was to evaluate leadadsorption using adsorption isotherms, kinetics and thermodynamics. Fourier TransformInfrared Sp...

This paper presents a kinetic model of the laccase-aided chlorine dioxide bleaching of bagasse pulp. The kinetic model was based on the rate of reduction of adsorbed organic halogen (AOX). The effects of the laccase enzyme dosage, the mediator 1-hydroxybenzotriazole (HBT) dosage, and the reaction temperature on the AOX content of the bleaching effluent are discussed. Good fits were obtained for...