Utilizing MoO3, MoO3 doped Y2O3 for heavy metals (Hg, Pb, Cu) removal from wastewater monitored by p-XRF and LIBS techniques

Abstract

In this study the heavy metals (Cu²⁺, Pb²⁺, Hg⁺²) were removed from waste water using two types of sorbents, namely, MoO₃ and MoO₃ doped with 12 %Y₂O₃ were synthesized by solgel method. The as-prepared oxides were characterized using X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS). A combination of quantitative and qualitative analysis techqnieus, portable X-ray fluorescence (pXRF) and laser-induced breakdown spectroscopy (LIBS) were used to evaluate the removing efficency. Calibration curves were performed to elucidate the limit of detection (LOD) of the Laser-Induced Breakdown Spectroscopy (LIBS) technique for the removal process The LOD were 1.65, 2–21 and 0.98 ppm for Cu, Pb and Hg respectively. The results indicated that the Y₂O₃-doped α-MoO₃ has a consistently greater removal efficiency compared to MoO₃. The removal effecieny of Hg²⁺, Pb²⁺ and Cu²⁺ was 95 %, 33 % and 21 % respectively with MoO₃ while it was 98 % 63 % 35 % for MoO₃ doped Y₂O₃, The results proved also that MoO₃ and MoO₃ doped Y₂O₃ nanoparticles can be utilized as cost effective adsorbent material for heavy metal removal in wastewater. The study showed the potential of using Laser-Induced Breakdown Spectroscopy (LIBS) in environmental applications.