Ultrafiltration

Ultrafiltration is a membrane filtration process in which pressure or a concentration gradient forces a liquid through a semipermeable membrane that retains high-molecular-weight material, such as proteins, on one side while water and smaller molecules pass through, and membranes are classified by the molecular weight cutoff at which they perform this separation. The process can run in cross-flow or dead-end mode and is valued because, unlike heat-based purification, it does not denature the proteins it concentrates; it is used across the chemical, pharmaceutical, and food industries, most notably in dairy processing to concentrate whey protein, as well as in enzyme recovery, industrial wastewater treatment, and drinking water treatment, where it can remove ninety to one hundred percent of pathogens. Membrane fouling, the gradual buildup of retained material on the membrane surface, is the process's main operating limitation, driving up costs through the need for frequent cleaning and membrane replacement. No single clean origin date or inventor is established in the source consulted.