How to Model Ion-Exchange Membranes and Donnan Potentials

Henrik Ekström August 29, 2018

Ion-exchange membranes are widely employed within the field of electrochemical engineering. In polymer electrolyte fuel cells and vanadium flow batteries, they are used to conduct ions and at the same time prevent reactants and electrons from crossing between the two flow compartments. The ability to promote the passage of ions of either positive or negative charge is also used in electrodialysis for cleaning water from ions. In this blog post, we will explore the ion-selective capabilities of ion-exchange membranes.

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Siva Sashank Tholeti August 22, 2018

Sparging, a mass transfer process between a gas and a liquid, is commonly encountered in industrial applications such as beverage carbonation and photobioreactors, or even at home for aeration in aquariums. In this blog post, we detail how to model a type of sparging, carbonation, using the COMSOL Multiphysics® software.

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Brianne Costa July 4, 2018

Multijet tubular reactors are used to manufacture polymers such as polyester. The turbulent flow that occurs in this type of reactor can affect the manufacturing process, including the reaction kinetics, fiber quality, conversion, and yield. By developing a reactor model that fully takes into account both the fluid dynamics and chemical reactions, you can optimize a reactor design for efficient and reliable polymer production.

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Thomas Forrister June 27, 2018

Batch reactors are used to manufacture a wide variety of products in the fine chemical, pharmaceutical, and food industries. In some cases, fine chemical processing may require more consistent operating conditions than batch reactors can offer, and continuous plate reactors may then provide better control of the process. Chemical modeling can help in the design of continuous plate reactors that are optimized for thermal control and product purity.

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Brianne Costa March 21, 2018

Pablo Rolandi from Amgen delivered a keynote presentation at the COMSOL Conference 2017 Boston. The topic? How Amgen is moving beyond modeling and simulation for biopharma development. Rolandi shared five examples that illustrate this idea across both biologic and synthetic medicine applications. If you missed his presentation, you can watch a recording of the video and read the highlights of what he discussed here.

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Edmund Dickinson January 26, 2018

Previously on the blog, we discussed why surfaces are sites of special chemical interest and discussed the theories used to describe reactions at surfaces, including when those surfaces are described within homogenized models of porous media. In this blog post, we’ll discuss how chemicals behave when they become attached to a surface by adsorption. Adsorption plays an essential role in many catalytic and sensing processes, so let’s consider how it can be built into your chemical models.

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Caty Fairclough January 5, 2018

Steam reformers are commonly used for power and energy generation processes. To accurately analyze the performance of a steam reformer design, you need to be able to couple mass, energy, and flow equations. Using the COMSOL Multiphysics® software, you can set up a model of a steam reformer that represents its real-world behavior and operating conditions.

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Ed Fontes December 26, 2017

You can easily describe composition- and temperature-dependent fluid properties using the thermodynamic properties database, available as of version 5.3a of the COMSOL Multiphysics® software. For reacting systems, the database computes enthalpy of formation and enthalpy of reaction. For fluid flow and heat and mass transfer, the database can compute viscosity, density, heat capacity, thermal conductivity, and diffusivity of liquids and gases. For systems with several phases, the thermodynamic properties database computes the composition of the phases at equilibrium.

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Edmund Dickinson October 10, 2017

In a previous blog post, we discussed why surfaces are special in chemical reactors. In this blog post, we’ll see how surface area is maximized in reactor structures such as pellet beds, and how we can simply and accurately simulate fixed-bed reactors in spite of their local geometric complexity and the importance of microscopic diffusion.

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Caty Fairclough August 15, 2017

Zone electrophoresis separates different species in a sample into distinct well-resolved peaks, giving scientists the ability to analyze substances like proteins and nucleic acids. Improving this electrophoretic separation technique requires us to accurately model the transport and separation of these species. Here, let’s look at how the COMSOL Multiphysics® software can be used to simulate the movement of species during zone electrophoresis.

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Edmund Dickinson July 13, 2017

In biophysics, electrochemistry, and the design of catalytic reactors, researchers and engineers exploit the special chemical and physical properties of solid surfaces involving both gas-solid and liquid-solid interfaces. This blog post discusses the basics of the kinetics of surface reactions at simple surfaces and how they can be modeled with the COMSOL Multiphysics® software. In a subsequent blog post, we will look at how mass transport and reaction kinetics at surfaces are described for homogenized porous media.

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