Microbial flocculants as an excellent alternative to synthetic flocculants for industrial application: A comprehensive review

Flocculation is used to effectively separate suspended colloids in domestic and industrial wastewater. Flocculants are classified into three categories as organic, inorganic and natural flocculants. Its flocculating properties, ease of use and commercial use have led to the widespread use of organic and inorganic flocculants. However, it can cause serious health problems due to its carcinogenicity and neurotoxicity. Therefore, natural bioflocculants are used to treat wastewater without harming humans and the environment. Natural flocculants are non-toxic, environmentally friendly and capable of flotation even at low concentrations. This article also discusses the classification, functions, mechanisms and applications of flocculants. Applications of natural flocculants and flocculation efficiency in the treatment of industrial wastes such as food, heavy metal and dyeing are discussed. Future studies will use methods to understand how agricultural and food wastes are used for cost-effective bioflocculant production. Bacterial consortia and new novel marine bacteria are indicated for large-scale industrial production.