Potential of biological materials for removing heavy metals from wastewater.

Agricultural products/by-products are natural sorbent materials that possess capacity for removing contaminants including heavy metals from wastewaters and hence can be exploited as replacement of costly methods for wastewater treatment. The sorption of heavy metals onto these biomaterials is attributed to constituent's proteins, carbohydrates, and phenolic compounds that contain functional groups such as carboxylate, hydroxyl, and amine. Natural efficiency of these materials for removing heavy metals can be enhanced by treating them with chemicals. The present review emphasizes their use in developing eco-friendly technology for a large-scale treatment of wastewater.