A Simple 1D Convection-Diffusion Model of Oxalic Acid Oxidation Using Reactive Electrochemical Membrane

In recent years, electrochemical methods utilizing reactive electrochemical membranes (REM) have been recognized as the most promising technologies for the removal of organic pollutants from water. In this paper, we propose a 1D convection-diffusion-reaction model concerning the transport and oxidation of oxalic acid (OA) and oxygen evolution in the flow-through electrochemical oxidation system with REM. It allows the determination of unknown parameters of the system by treatment of experimental data and predicts the behavior of the electrolysis setup. There is a good agreement in calculated and experimental data at different transmembrane pressures and initial concentrations of OA. The model provides an understanding of the processes occurring in the system and gives the concentration, current density, potential, and overpotential distributions in REM. The dispersion coefficient was determined as a fitting parameter and it is in good agreement with literary data for similar REMs. It is shown that the oxygen evolution reaction plays an important role in the process even under the kinetic limit, and its contribution decreases with increasing total organic carbon flux through the REM.

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A Simple 1D Convection-Diffusion Model of Oxalic Acid Oxidation Using Reactive Electrochemical Membrane

10.20944/preprints202105.0678.v1 ◽

2021 ◽

Author(s):

Ekaterina Skolotneva ◽

Marc Cretin ◽

Semyon Mareev

Keyword(s):

Experimental Data ◽

Oxalic Acid ◽

Oxygen Evolution ◽

Reaction Model ◽

Diffusion Reaction ◽

Acid Oxidation ◽

Unknown Parameters ◽

Convection Diffusion ◽

Organic Carbon Flux ◽

Good Agreement

In recent years, electrochemical methods utilizing reactive electrochemical membranes (REM) have been recognized as the most promising technologies for the removal of organic pollutants from water. In this paper, we propose a 1D convection-diffusion-reaction model concerning the transport and oxidation of oxalic acid (OA) and oxygen evolution in the flow-through electrochemical oxidation system with REM. It allows the determination of unknown parameters of the system by treatment of experimental data and predicts the behavior of the electrolysis setup. There is a good agreement in calculated and experimental data at different transmembrane pressures and initial concentrations of OA. The model provides an understanding of the processes occurring in the system and gives the concentration, current density, potential and overpotential distributions in REM. The dispersion coefficient was determined as a fitting parameter and it is in good agreement with literary data for similar REMs. It is shown, that the oxygen evolution reaction plays an important role in the process even under the kinetic limit, and its contribution decreases with increasing total organic carbon flux through the REM.

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A 2D Convection-Diffusion Model of Anodic Oxidation of Organic Compounds Mediated by Hydroxyl Radicals Using Porous Reactive Electrochemical Membrane

Membranes ◽

10.3390/membranes10050102 ◽

2020 ◽

Vol 10 (5) ◽

pp. 102 ◽

Cited By ~ 1

Author(s):

Ekaterina Skolotneva ◽

Clement Trellu ◽

Marc Cretin ◽

Semyon Mareev

Keyword(s):

Organic Compounds ◽

Hydroxyl Radicals ◽

Current Density ◽

Current Density Distribution ◽

Reaction Model ◽

Diffusion Reaction ◽

Unknown Parameters ◽

Distribution Profile ◽

Convection Diffusion ◽

Oxidation Of Organic Compounds

In recent years, electrochemical methods utilizing reactive electrochemical membranes (REM) have been considered as a promising technology for efficient degradation and mineralization of organic compounds in natural, industrial and municipal wastewaters. In this paper, we propose a two-dimensional (2D) convection-diffusion-reaction model concerning the transport and reaction of organic species with hydroxyl radicals generated at a TiOx REM operated in flow-through mode. It allows the determination of unknown parameters of the system by treatment of experimental data and predicts the behavior of the electrolysis setup. There is a good agreement in the calculated and experimental degradation rate of a model pollutant at different permeate fluxes and current densities. The model also provides an understanding of the current density distribution over an electrically heterogeneous surface and its effect on the distribution profile of hydroxyl radicals and diluted species. It was shown that the percentage of the removal of paracetamol increases with decreasing the pore radius and/or increasing the porosity. The effect becomes more pronounced as the current density increases. The model highlights how convection, diffusion and reaction limitations have to be taken into consideration for understanding the effectiveness of the process.

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Development of a convection-diffusion-reaction model for solving Maxwell's equations in frequency domain

International Journal for Numerical Methods in Fluids ◽

10.1002/fld.2567 ◽

2011 ◽

Vol 69 (2) ◽

pp. 430-441

Author(s):

Tony W. H. Sheu ◽

K. C. Lin ◽

J. H. Li

Keyword(s):

Frequency Domain ◽

Maxwell’S Equations ◽

Maxwell's Equations ◽

Reaction Model ◽

Diffusion Reaction ◽

Convection Diffusion

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Analytical study of effects of finger-growth velocity on reaction characteristics of reactive miscible viscous fingering by using a convection–diffusion–reaction model

Chemical Engineering Science ◽

10.1016/j.ces.2004.05.019 ◽

2004 ◽

Vol 59 (18) ◽

pp. 3817-3826 ◽

Cited By ~ 11

Author(s):

Yuichiro Nagatsu ◽

Toshihisa Ueda

Keyword(s):

Growth Velocity ◽

Analytical Study ◽

Viscous Fingering ◽

Reaction Model ◽

Diffusion Reaction ◽

Convection Diffusion ◽

Reaction Characteristics

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Implicit-Explicit Methods for a Convection-Diffusion-Reaction Model of the Propagation of Forest Fires

Mathematics ◽

10.3390/math8061034 ◽

2020 ◽

Vol 8 (6) ◽

pp. 1034 ◽

Cited By ~ 1

Author(s):

Raimund Bürger ◽

Elvis Gavilán ◽

Daniel Inzunza ◽

Pep Mulet ◽

Luis Miguel Villada

Keyword(s):

Forest Fires ◽

Control Strategies ◽

Reaction Diffusion ◽

Reaction Model ◽

Diffusion Reaction ◽

Nonlinear Convection ◽

Splitting Technique ◽

Convection Diffusion ◽

Fuel Density ◽

Diffusion Convection

Numerical techniques for approximate solution of a system of reaction-diffusion-convection partial differential equations modeling the evolution of temperature and fuel density in a wildfire are proposed. These schemes combine linearly implicit-explicit Runge–Kutta (IMEX-RK) methods and Strang-type splitting technique to adequately handle the non-linear parabolic term and the stiffness in the reactive part. Weighted essentially non-oscillatory (WENO) reconstructions are applied to the discretization of the nonlinear convection term. Examples are focused on the applicative problem of determining the width of a firebreak to prevent the propagation of forest fires. Results illustrate that the model and numerical scheme provide an effective tool for defining that width and the parameters for control strategies of wildland fires.

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Polymerase chain reaction in natural convection systems: A convection-diffusion-reaction model

EPL (Europhysics Letters) ◽

10.1209/epl/i2005-10171-6 ◽

2005 ◽

Vol 71 (6) ◽

pp. 1008-1014 ◽

Cited By ~ 16

Author(s):

E Yariv ◽

G Ben-Dov ◽

K. D Dorfman

Keyword(s):

Polymerase Chain Reaction ◽

Natural Convection ◽

Reaction Model ◽

Diffusion Reaction ◽

Chain Reaction ◽

Convection Diffusion ◽

Polymerase Chain

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A generalized 1-dimensional particle transport method for convection diffusion reaction model

Afrika Matematika ◽

10.1007/s13370-011-0007-0 ◽

2011 ◽

Vol 23 (1) ◽

pp. 21-39 ◽

Cited By ~ 3

Author(s):

James Makungu ◽

Heikki Haario ◽

William Charles Mahera

Keyword(s):

Particle Transport ◽

Reaction Model ◽

Diffusion Reaction ◽

Convection Diffusion ◽

Transport Method

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An Energy Model for Fatigue Life Prediction of Composite Materials Using Continuum Damage Mechanics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.1353 ◽

2011 ◽

Vol 110-116 ◽

pp. 1353-1360 ◽

Cited By ~ 3

Author(s):

A. Movaghghar ◽

G. I. Lvov

Keyword(s):

Experimental Data ◽

Fatigue Life ◽

Damage Mechanics ◽

Continuum Damage Mechanics ◽

Unidirectional Composite ◽

Energy Model ◽

Unknown Parameters ◽

Elastic Symmetry ◽

Principal Directions ◽

Good Agreement

In this paper an energy-based model for predicting fatigue life and evaluation of progressive damage using plane-stress assumption is proposed. This model allows us to predict fatigue durability taking into account principal directions of the stress tensor relative to planes of elastic symmetry of material. First, the unknown parameters of this model will be calculated for three different composites with various lays-up. Method for determining these parameters is based on the minimum necessary set of experimental data. Afterwards the model was used to predict fatigue life and estimate accumulated fatigue damage in a unidirectional composite under different angles of loading. The analysis of conclusions of the theory for various loading conditions was carried out and performed comparison between the experimental data and predicted results. The predicted fatigue lives obtained by the proposed energy model were in good agreement with the experimental data.

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Solution of Boundary Value Problems Using Dual Reciprocity Boundary Element Method

Advances in Applied Mathematics and Mechanics ◽

10.4208/aamm.2014.m783 ◽

2017 ◽

Vol 9 (3) ◽

pp. 680-697 ◽

Cited By ~ 1

Author(s):

Hassan Zakerdoost ◽

Hassan Ghassemi ◽

Mehdi Iranmanesh

Keyword(s):

Integral Equation ◽

Boundary Element Method ◽

Boundary Element ◽

Analytic Solutions ◽

Boundary Integral ◽

Diffusion Reaction ◽

Convection Diffusion ◽

Reaction Equations ◽

Good Agreement ◽

Element Method

AbstractIn this work we utilize the boundary integral equation and the Dual Reciprocity Boundary Element Method (DRBEM) for the solution of the steady state convection-diffusion-reaction equations with variable convective coefficients in two-dimension. The DRBEM is a numerical method to transform the domain integrals into the boundary only integrals by using the fundamental solution of Helmholtz equation. Some examples are calculated to confirm the accuracy of the approach. The results obtained by the analytic solutions are in good agreement with ones provided by the DRBEM technique.

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