Wastewater treatment using Moringa oleifera (Lam.) and Eichhornia crassipes (Mart.) as neutral-carbon options within the framework of COP 27 recommendations

Contamination of water by heavy toxic metal ions such as (e.g., Cr⁶⁺, Mn²⁺, Ni²⁺, Cu²⁺, Zn²⁺, As³⁺ Pb²⁺, Cd²⁺, and Ag⁺) can lead to serious environmental and human health problems because of their acute and chronic toxicity to the biological system. In recent decades, research has been directed to alternative production of cheaper sustainable ecofriendly adsorbents with low carbon footprints. Moringa oleifera as an example for terrestrial plant and Eichhornia crassipes commonly known as water hyacinth (WH) as an aquatic plant, are simple effective natural and powerful adsorbents for heavy metals removal. Both plants have invasive growth tendency. They can be easily utilized in developed communities and in rural areas to produce clean water. This review is a comprehensive summary of M. oleifera (MO) and E. crassipes (WH) uses in impure water treatments with a particular attention to their role in reducing carbon footprint. PubMed, Science Direct and Springer were the search data engines that the article referred to from the years 2009–2023.