Ultrafiltration: a practical overview

Published on January 30, 2020   32 min

A selection of talks on Methods

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Hello. I am Mahsa Hadidi and I'm going to give a practical overview of ultrafiltration in biotechnology industry.
In this short presentation today, I will give an overview of ultrafiltration, its function, operation, and modules. I will also talk about fouling, permeability, and concentration polarization effect, plus ultrafiltration system control and optimization, and finally, system yield and recovery.
What is membrane-based filtration? Membrane filtration is a unit operation working primarily on the principles of size-based separations. Membranes are porous materials that let smaller molecules than their pores pass through while retaining larger molecules. Use of membrane processes in bio separations dates back to early 19th Century when they were mostly used for analytical purposes due to limitations on available membranes and modules. In early days, membranes also played an important role in purification of biotechnology products by adopting the process from other industries, such as food, dairy, and water industries. Over the past couple of decades, development of new membranes, modules, and systems have led to extensive use of filtration processes in biotechnology industry. Membrane-based filtration processes can be divided into subcategories based on their application. Microfiltration membranes have pore sizes between 50 nanometer and 10 micron, so they retain cell and bacteria while allow proteins, viruses, macromolecules, sugars, salts, and water to pass through. Virus filtration membranes are specifically designed to retain viruses with 20-70 nanometer size range. Ultrafiltration membranes retain proteins and macro-molecules with pore sizes between one and 20 nanometer, but allow sugars and salts to pass through. Nanofiltration membranes are designed to separate divalent salt and larger species from solvent, monovalent salts and smaller organics while reverse osmosis membranes retain smaller than one nanometer salt molecules and only allow water molecules to permeate, thus are extensively used in production of high-quality water, also known as water for injection. In this presentation, I'm going to focus on ultrafiltration as it is a unique step present in the process of almost all byproducts.