Use of coir fibers for water and air filters

As a part of a large productive system with considerable added value, especially in the food-related industry, coir fibers from coconut palm fruit hair can be perceived as a by-product, if not waste, which is available for a number of applications. The thick aspect of these fibers with a considerable amount of lignin and a microfibrillar angle approaching 45°, suggests their use in geotextiles for soil amendment and as the consequence also in filters both to depurate air and wastewater. This review discusses their possible application in the filtering field, shedding light on the relation with coir with the productive system of coconut, and in the understanding that scientific literature on this topic is gradually coming out, although in most cases the construction of coir-containing filters appears as a matter of expediency and therefore further investigations will be needed in the near future, if these are going to appear with a stronger position to rule over the market.