Removal efficiency of heavy metals from wastewater by plant-derived nanoparticles. Case study of minechma subsessile (umubazi) and gomphocarpus fruticosus (gasaho)

Abstract

Environmental health problems caused by heavy metals are enumerous of which cancer is leading. The getting rid of heavy metals by the use of inexpensive technologies have intensively searched for and is still ongoing while focussing at various metals. The elimination of them from wastewater using plant-derived nanoparticles is the most promising technology that has been thoroughly explored because of its easy application, broad applicability, high removal. The study described here sought to determine how well plant-derived nanoparticles removed specific heavy metals from wastewater. After taking into account the heavy elements such as lead, cadmium, chromium, iron, and zinc, an extract of M. subsessile and G. fruticosus was made by maceration in the mixture of Methanol: Dichloromethane 1:1. The CuO-nanoparticles and Ag-nanoparticles were synthesized and charactered by using the Fourier Transform Infra-Red (FTIR) spectroscopy technique. Heavy metals removal efficiency was assessed by using Microwave Plasma Atomic Emission Spectroscopy (MP AES). According to experimental findings, the effectiveness of removing heavy metals in wastewater is influenced by a type of nanoparticles, pH, adsorbent dose, plant derailing the nanoparticle, and contact time. The NPs with M. subsessile have a higher adsorption capability to heavy metals than the NPs with G. fruticosus, which means they remove more heavy metals from wastewater. This may indicate that the NPs derived from M. subsessile extract are very porous, characterized with larger surface area, and feature an active functional group that is involved to trap the heavy metal elements As contact duration increased, more heavy metals were removed because the nanoparticles had more opportunity to adsorb to the metal. The majority of heavy metals were completely eliminated after 24 h, according to this research. This study shows that metal ion adsorption increases significantly with the pH from low to high. Furthermore, CuO-NP was found to be an effective nano-sorbent, reducing the levels of Cd, Fe, Cr (VI), Co, Pb, and Fe in wastewater