Membrane filtration is a process that uses a semi-permeable membrane to separate particles from liquids. This technique allows smaller molecules, such as water and certain solutes, to pass through while blocking larger particles, including bacteria and suspended solids. It is commonly used in water treatment, food processing, and pharmaceuticals to ensure product purity. There are different types of membrane filtration, including microfiltration, ultrafiltration, nanofiltration, and reverse osmosis. Each type has varying pore sizes, which determine what can be filtered out. This technology is efficient and can help improve the quality of liquids by removing unwanted contaminants.