Unleashing the power of plant-based modified starch as a game-changing natural coagulant

Recently, researchers are racing to introduce novel, natural, and non-toxic coagulants for effective wastewater treatment without adversely impacting the environment. Extensive research on the utilization of natural compounds for wastewater treatment has garnered attention due to the toxic reaction of the chemical-based water treatment agents and their by-products. Plant seed extracts, chitosan, alginate, starch, tannins, cactus mucilage, and agricultural wastes are some of the natural compounds that have been identified for effective wastewater treatment. Although these natural compounds are beneficial in wastewater treatment, their stability in aqueous mediums remain a major concern to be utilized for large-scale water treatment plants. Among these natural compounds, starch-derived coagulants are gaining recognition in the field of water treatment due to presence of unique functional groups, such as carboxyl and hydroxyl groups that are attached to their polysaccharide ring, post effective modification. Hence, this review provides an overview of recent progress of natural coagulants in the field of flocculation and coagulation studies. It also discusses modification techniques applied to various types of starch that have been identified to be effective in the treatment of both turbid water and their potential as an effective disinfectant.