Efficient Removal of Cationic and Anionic Dyes from Synthetic and Real Wastewater by Plant-mediated Nickel Nanoparticles

Abstract

In this study, Ni NPs were produced by biosynthesis method with the help of phytoconstituents present in the Sahadevi plant (Vernonia cinerea) ethanoic extract namely Sahadevi nickel nanoparticles (SNPs). SNPs were characterized using XRD, FT-IR, HR-FESEM. XRD study shows crystalline nature of SNPs. SNPs were employed as bioadsorbent for the elimination of dyes like cationic (BG) and anionic (CR) dyes from aqueous media. Adsorption capacity of SNPs was analyzed in batch modes at various pH, initial dye concentration, contact time, isotherm, and kinetics. The maximum adsorption capacity (qm) shown in Langmuir isotherm was obtained as 1666.7 mg g-1 in case of BG dye and 666.7 mg g-1 in CR dye, respectively. The higher value of coefficient of Langmuir isotherm recommended monolayer adsorption. Adsorption kinetics information was valuable suited to pseudo-second order kinetics with R2 > 0.99 for both dyes. SNPs proved to be an efficient sorbent for the elimination of dyes from aqueous media and can be employed to remove textile and tannery discharges. Overall, this study suggests that the use of SNPs is safe and secure, eco-friendly, cost-effective, which can be used as bioadsorbent removing colored organic effluents as dyes from water bodies.