Phycoremediation of emerging contaminants and heavy metals from industrial wastewater: A sustainable green approach for bioeconomy

Phycoremediation of emerging pollutants and heavy metals for treatment technologies is attracted mainly due to low-energy, cost-effective, sustainable, and eco-friendly solutions. Microalgae appear to be a promising candidate for pollutant biosorption and bioaccumulation, with excellent removal potential. However, the right selection of microalgae species for the degradation of specific pollutants remains a major challenge. Phycoremediation could be combined with the existing industrial treatment processes of wastewater as an effective secondary or tertiary stage process, which would enhance the treatment efficiency. This review focuses on the recent trends in bioremediation of wastewater treatment for heavy metals and emerging contaminants' removal, factors influencing pollutant removal, and mechanisms of pollutant degradation. Microalgae efficiently eliminated nutrients along with heavy metals and emerging pollutants up to 83-96 %, 43-100 %, and 18-100 % from different wastewaters. Furthermore, valorization of microalgal biomass for the bioeconomy, challenges associated with wastewater cultivation, and prospects are discussed. This review aims to provide useful information that will aid in the development of commercially viable technological interventions for microalgae-based bioremediation processes in sustainable environments.