Model Electroanalysis, Electrolysis, and Electrodialysis with the Electrochemistry Module
From the Lab Researcher to the Industrial Electrochemical Engineer
The Electrochemistry Module expands the possibilities in designing, understanding, and optimizing electrochemical systems through accurate simulation. This product offers significant benefit to researchers in the lab or to the industrial electrochemical engineer. Capabilities such as modeling electrochemical reaction mechanisms, mass transport, and current density distributions enable efficient simulation for applications including electrolysis, electrodialysis, electroanalysis, electrochemical sensors, and bioelectrochemistry.
Interfaces for Primary, Secondary and Tertiary Current Distributions
The Electrochemistry Module covers a wide range of applications involving electrochemical reactions. This is accomplished through interfaces for primary, secondary, and tertiary current distributions; electroanalysis; flow in free and porous media; heat transfer; heterogeneous and homogeneous chemical reactions; and material transport in dilute and concentrated solutions. Possible applications include the study and design of chlor-alkali and chlorate electrolysis, water electrolysis for hydrogen and oxygen production, waste water treatment, desalination of seawater, fundamental electrochemical studies in electrocatalysis and electroanalysis, and sensors for glucose, pH, hydrogen, and other gases.
- Secondary current distribution in a unit chlor-alkali cell.
- You can model the charge density in diffuse double layers without having to assume for charge neutrality by coupling Poisson's equation for the potential to the Nernst-Planck equations for ion transport.
- Nyquist plot for a range of frequencies and electrode kinetic heterogeneous rate constants.
Interfaces for Electrochemical Analysis
Dedicated features in the Electrochemistry Module enable the simulation of amperometry, potentiometry, electrochemical impedance, and coulometry studies, in addition to an interface provided specifically for cyclic voltammetry. Properties such as exchange current densities, charge transfer coefficients, specific active surface areas, diffusivities, and reaction mechanisms can be determined from combined experiment and simulation results. These can subsequently be used in industrial applications for accurate modeling and design optimization.
Complete Support for Applications Involving Electrochemical Reactions
Interfaces embedded in the Electrochemistry Module enable the modeling of systems assuming primary, secondary, or tertiary current distributions. The primary current distribution utilizes Ohm's Law together with a charge balance to model the flow of current in both the electrolyte and electrodes, while assuming that losses in electric potential due to the electrochemical reactions are negligible. The secondary current distribution includes these reaction-based losses and is modeled through interfaces for the Tafel and Butler-Volmer equations. These also support modifications and custom expressions. The interfaces include electric potential as part of the electrochemical reaction kinetics.
In many reacting systems, and in close proximity to the electrodes, the concentration of the electrolyte is not constant. In that case, the effects of diffusion and convection have to be considered in addition to migration. The Electrochemistry Module provides an interface for tertiary current distributions that utilizes the Nernst-Planck equation to describe the transport of chemical species in the electrolyte. Utilizing the unparalleled capabilities in COMSOL Multiphysics, this interface can be seamlessly coupled to other interfaces that describe fluid flow and heat transfer.
Modeling the Electrochemistry of Blood Glucose Test Strips
Stephen Mackintosh Lifescan Scotland UK
Lifescan Scotland is a medical device company that designs and manufactures blood glucose monitoring kits for the global diabetes market. These involve the self-monitoring of blood glucose levels through specialized monitoring systems and test strips that comprise of a plastic substrate, two carbon-based electrodes, a thin dry reagent layer, and ...
Electrochemical Treatment of Tumors
This model incorporates the transport and electrolytic reaction in the treatment of tumor tissue. Oxygen evolution at the anode produces protons, which lowers the pH, while chlorine production also leads to lowered pH through the hydrolysis of chlorine. One effect of a low pH is the permanent destruction of haemoglobin in the tissue, resulting ...
Diffuse Double Layer With Charge Transfer
In the diffuse double layer and within the first few nanometers of an electrode surface, the assumption of electroneutrality is not valid due to charge separation. Typically, the diffuse double layer may be of interest when modeling very thin layers of electrolyte including those in electrochemical capacitors and microelectrodes. This example ...
Desalination in an Electrodialysis Cell
Electrodialysis is a separation process for electrolytes based on the use of electric fields and ion selective membranes. Some common applications of the electrodialysis process are: - Desalination of process streams, effluents, and drinking water - pH regulation in order to remove acids from, for example, fruit juices and wines - ...
The electrochemical cell shown in this model can be regarded as a unit cell of a larger wire-mesh electrode that is common in many industrial processes. One of the most important aspects in the design of electrochemical cells is the current density distributions in the electrolyte and electrodes. Non-uniform current density distributions can be ...
Current Distribution in a Chlor-Alkali Membrane Cell
The chlor-alkali membrane process is one of the largest in industrial electrolysis with the production of roughly 40 million metric tons of both chlorine and caustic soda per year. Chlorine is used predominantly for the production of vinyl chloride monomer, which in turn is used for the production of poly vinyl chloride (PVC). Current density in ...
Cyclic voltammetry is a common analytical technique for investigating electrochemical systems. In this method, the potential difference between a working electrode and a reference electrode is swept linearly in time from a start potential to a vertex potential, and back again. The current-voltage waveform, called a voltammogram, provides ...
Electrochemical Impedance Spectroscopy
Electrochemical impedance spectroscopy (EIS) is a common technique in electroanalysis. It is used to study the harmonic response of an electrochemical system. A small, sinusoidal variation is applied to the potential at the working electrode, and the resulting current is analyzed in the frequency domain. The real and imaginary components of the ...