Metal biosorption onto non-living algae: a critical review on metal recovery from wastewater

Abstract

The widespread occurrence of metals in water bodies has been fueling the development of platforms for removing and recovering these elements. Biosorption has emerged as a potential tool for metal removal from wastewater. Among the available biosorbents, algae have been highlighted as a sustainable and cost-effective sorbent. Despite the blooming interest in this field, most studies comprise transversal gaps that prevent it from progressing. Herein, the application of non-living algae for metal recovery from wastewater is discussed. Limitations such as rudimentary cultivation, water decontamination emphasis in detriment to metal recovery and lack of reports contemplating ion and metal competition are addressed. Due to the limited number of studies conducted in natural wastewater, a practical application of non-living Sargassum sp. into acid mine drainage is shown. The obtained sorption capacity values are compared with those from other wastewater to evaluate the potential of non-living algae for metal sorption in real matrices. A critical review on the cost performance of algae as opposed to commercial and waste-based sorbents is presented.