Filtrato

Filtrato is the Italian term for the liquid or gas that has passed through a filter, i.e., the product of a filtration process. It is also used as an adjective meaning filtered. The related noun for the filter medium is filtrante, while filtrazione denotes the process itself. The word derives from filtrare, from Latin filtrare.

In practical terms, filtration separates solids from liquids (or gases) by means of a porous barrier. The material that passes through the filter is the filtrato, while the material retained on the filter is the residuo. Depending on the pore size and the filter type, different fractions are obtained. Common laboratory and industrial examples include coffee or wine filtration, water treatment, and the purification of chemical solutions. The filtrato may contain dissolved substances that are not removed by the filter.

In biology and medicine, filtration concepts appear in physiology as well. The term filtrato is used to describe the fluid formed by processes such as glomerular filtration in the kidney. The filtrato glomerulare contains water and small solutes but not large proteins, and it is subsequently modified by reabsorption and secretion to form urine. The idea extends to other biological and biochemical contexts where a liquid passes through a barrier to separate components.

In environmental engineering and industry, filtration and the resulting filtrato are central to water purification, air cleaning, and product processing. The efficiency of filtration depends on filter material, pore size, pressure, and the properties of the substances involved.