Use of Algae for Wastewater Treatment Containing Heavy Metals

Wastewater treatment is a critical environmental issue particularly when it comes to the removal of heavy metals.

These contaminants often originating from industrial processes, mining activities and agricultural runoff pose significant risks to both ecosystems and human health. Conventional methods for removing heavy metals from wastewater can be costly and sometimes ineffective. In recent years there has been growing interest in the use of algae as a sustainable and efficient solution for wastewater treatment. This article explores the potential of algae in treating wastewater containing heavy metals examining their mechanisms benefits and challenges.

Mechanisms of Algal Treatment

Algae primarily microalgae and macroalgae have shown great potential in absorbing and accumulating heavy metals from wastewater. The mechanisms by which algae achieve this can be broadly categorized into biosorption and bioaccumulation.

Biosorption: Biosorption involves the passive binding of heavy metals to the surface of algal cells. This process is largely driven by the cell wall components such as polysaccharides, proteins and lipids which contain functional groups capable of binding metal ions. The efficiency of biosorption depends on various factors including the type of algae the nature of the heavy metals, pH, temperature and contact time. Algae such as Chlorella vulgaris and Spirulina platensis have demonstrated high biosorption capacities for metals like cadmium, lead and chromium.

Bioaccumulation: Bioaccumulation refers to the active absorption and internalization of toxic substances by algae cells. This process involves the transport of metal ions across the cell membrane and their subsequent sequestration in intracellular compartments.