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Predicting Reactants’ Hydrodynamic Behavior Inside Non-Porous Catalytic Reactors
Issue:
Volume 2, Issue 6, November 2014
Pages:
71-75
Received:
16 September 2014
Accepted:
13 October 2014
Published:
20 October 2014
Abstract: Gaseous reactants usually have complex behaviors ranging from unsteady flow patterns to oscillations due to the differences in various physical and chemical properties. Such behaviors hinder the complete understanding coupled between transport processes and chemical kinetics. Systems within which chemical reactions are coupled with diffusion and convective transport have chemical engineering applications. The aim of the present work is to simulate the steady state behavior of a reaction-diffusion-convection system using the finite element method for ammonia decomposition. The overall model used consists of the flow and mass transport modules which are described by the continuity, Stokes equations and the convective dispersion equation respectively. Concentration profile, velocity and pressure fields presented are for a first order reaction for ammonia decomposition inside tubular non-porous catalytic reactors. Two different types of reactors are considered, the first one represents a fuel cell and the second is for a catalytic wall reactor.
Abstract: Gaseous reactants usually have complex behaviors ranging from unsteady flow patterns to oscillations due to the differences in various physical and chemical properties. Such behaviors hinder the complete understanding coupled between transport processes and chemical kinetics. Systems within which chemical reactions are coupled with diffusion and co...
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Densities and Partial Molar Volumes of Dodecyltrimethylammonium Bromide in Binary Systems (Methanol+Water) at T=(298.15 to 323.15) K
Sujit Kumar Shah,
Ajaya Bhattarai,
Sujeet Kumar Chatterjee
Issue:
Volume 2, Issue 6, November 2014
Pages:
76-85
Received:
14 October 2014
Accepted:
27 October 2014
Published:
30 October 2014
Abstract: The densities of dodecyltrimethylammonium bromide in pure water and in methanol + water mixed solvent media containing (0.10, 0.20, 0.30, and 0.40) volume fractions of methanol were measured at (298.15, 308.15, 318.15, and 323.15) K. The concentrations are varied from (0.4 10-1 to 1.2 10-1) mol kg-1. The results showed almost increase on the densities with increasing surfactant concentration. Also, the densities are found to decrease with increasing temperature over the entire concentration range investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The effects of concentration, solvent composition and temperature on the partial molar volumes are discussed.
Abstract: The densities of dodecyltrimethylammonium bromide in pure water and in methanol + water mixed solvent media containing (0.10, 0.20, 0.30, and 0.40) volume fractions of methanol were measured at (298.15, 308.15, 318.15, and 323.15) K. The concentrations are varied from (0.4 10-1 to 1.2 10-1) mol kg-1. The results showed almost increase on the dens...
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Removal of Copper and Fluoride from Wastewater by the Coupling of Electrocoagulation, Fluidized Bed and Micro-Electrolysis (EC/FB/ME) Process
Vo Anh Khue,
Li Tian Guo,
Xu Xiao Jun,
Yue Xiu Lin,
Peng Rui Hao
Issue:
Volume 2, Issue 6, November 2014
Pages:
86-91
Received:
7 November 2014
Accepted:
12 November 2014
Published:
20 November 2014
Abstract: Copper and fluoride ions were removed from wastewater by the coupling of electrocoagulation, fluidized bed and micro-electrolysis (EC/FB/ME) process. The results indicate that the use of aluminum electrode for simultaneous removal of copper and fluoride ions is better than iron electrode. By the orthogonal experiments study of the main factors influencing the efficiency of the treatment process, the best control parameters of this process were achieved in four aluminum electrodes, an initial pH of 5.0, a hydraulic retention time of 30 minutes, an applied voltage of 5V, a mass of iron-carbon (Fe/C) of 45g and the particle diameter of Fe/C of 20-27 mesh. With these conditions and the initial concentration of ions of 50mg/L, the residual concentration of copper and fluoride are 0.205 mg/L and 2.936 mg/L, respectively. The EC/FB/ME process is suitable for treatment of wastewater that fluoride concentration is less than 50 mg/L and copper concentration is less than 200 mg/L. This process was successfully applied to the treatment of a smelting wastewater sample.
Abstract: Copper and fluoride ions were removed from wastewater by the coupling of electrocoagulation, fluidized bed and micro-electrolysis (EC/FB/ME) process. The results indicate that the use of aluminum electrode for simultaneous removal of copper and fluoride ions is better than iron electrode. By the orthogonal experiments study of the main factors infl...
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Use of Agriculture-Based Waste for Basic Dye Sorption from Aqueous Solution: Kinetics and Isotherm Studies
Eman A. Ashour,
Maha A. Tony,
Patrick J. Purcell
Issue:
Volume 2, Issue 6, November 2014
Pages:
92-98
Received:
30 November 2014
Accepted:
14 December 2014
Published:
19 December 2014
Abstract: Low-cost bare palm branches were prepared as a sorbent for methylene blue dye from aqueous solution. The effect of reaction parameters such as sorbent dose and its particle size, initial dye concentration and the medium temperature were investigated using a batch sorption technique. Additionally, the maximum saturated monolayer sorption capacity of bare palm branches for methylene blue dye was investigated. The isotherm data was well-described by the Freundlich equation. Based on the adsorption capacity, it was shown that the use of bare palm branches was a promising low-cost agriculture waste material for the adsorption of dyes from aqueous solutions. Kinetic parameters of adsorption such as the rate constant and the intra-particle diffusion rate constant were determined. The principal conclusions of the study were that the reaction follows the pseudo-second order reaction kinetics.
Abstract: Low-cost bare palm branches were prepared as a sorbent for methylene blue dye from aqueous solution. The effect of reaction parameters such as sorbent dose and its particle size, initial dye concentration and the medium temperature were investigated using a batch sorption technique. Additionally, the maximum saturated monolayer sorption capacity of...
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