Synthesis and application of biocompatible nontoxic nanoparticles for reclamation of Ce³⁺ from synthetic wastewater: Toxicity assessment, kinetic, isotherm and thermodynamic study

The aim of present study is to synthesize forsterite nanoparticles (FRST) for the reclamation of cerium ions (Ce³⁺) from synthetic wastewater. The aim to synthesize FRST nanoparticles is due to its biocompatible and nontoxic nature. The formation of nanoparticles with average diameter of 58 nm was confirmed by TEM analysis. SEM images of bare FRST nanoparticles show a heterogeneous surface with porous nature. BET surface area of FRST nanoparticles is calculated to be 33.69 m²/g. The significant uptake of Ce³⁺ ions can be obtained for all the selected concentrations (25–150 mg/L) within 2 h of adsorbent–adsorbate interaction. The pH study shows that by increasing pH from acidic to alkaline range, higher removal can be achieved. Temperature study demonstrates the endothermic nature of Ce³⁺ adsorption. The value of sticking probability suggests very high sticking probability of Ce³⁺ ion for FRST nanoparticles. Ce³⁺ uptake is favored by higher temperature and with the increase in temperature from 298 to 328 K, Langmuir adsorption capacity increases from 36.45 to 42.99 m²/g. Applicability of FRST nanoparticles was also investigated for other light and heavy rare earth elements in single solute and multisolute systems. FRST nanoparticles show the significant removal of divalent metallic pollutants as well. The assessment of chemical toxicity of treated wastewater was carried out with the bioluminescent photobacterium (Vibrio fischeri) and decreased toxicity was observed in treated water samples. The outcome of present study suggests that the FRST nanoparticles can be efficiently utilized for the removal of Ce³⁺ ions and a wide range of other pollutant species as well.