Plant-Based Flocculants for Sustainable Wastewater Treatment: A mini Review of Applications, Research Trends, and Future Perspectives

The increasing issues of water scarcity and growing environmental pollution have led to the need for developing efficient methods for wastewater treatment. Coagulation-flocculation is one of the most known and cost-effective methods for the removal of suspended solids and various pollutants. Plant-based flocculants have recently been gaining popularity since they are environmentally friendly alternatives to conventional flocculants due to their biodegradability, low toxicity, high availability, and low price. The purpose of this review is to provide an overview of the plant-based flocculants that have been studied in the literature. The analysis has allowed for identifying the mechanisms of coagulation and flocculation, the characteristics of widely used flocculants based on plant materials, and their performance when treating different kinds of wastewater. The results indicate that agricultural residues and food waste such as banana peel, pomegranate peel, and pistachio shell are promising as natural flocculants; however, their efficiency is highly dependent on wastewater characteristics and running conditions, thus demonstrating that not a single plant-based flocculant can be applied to all kinds of wastewater treatment. Moreover, there is a lack of comparative studies in the literature on different types of wastewater. Overall, this review provides the results of recent studies in the analyzed area.

کلیدواژه ها:

Plant-based flocculants ، Wastewater treatment ، Plant-derived coagulants ، Coagulation–flocculation ، Sustainable wastewater treatment