Synthesis of a Novel Polymer-Assisted AlNiMn Nanomaterial for Efficient Removal of Sulfate Ions from Contaminated Water

Fouling by sulfate ion contamination constitutes a serious problem in the wastewater treatment industry. In this study, we synthesized polymer-assisted metallic nanomaterial and evaluated its adsorption capacity for the removal of sulfate ions from model contaminated water. The surface structural morphology, chemical, elemental, and mineralogical features, as well as functional group interaction of the polyvinyl pyrrolidone (PVP) with the AlNiMn nanomaterial, were ascertained with Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray Spectroscopy (EDX), X-ray dispersive (XRD), Fourier Transform Infra-red spectroscopy (FTIR). The batch adsorption experiments were carried out to determine the effects of solution pH, agitation speed, the adsorbent dosage, and contact time for the removal of sulfate ions from the synthesized contaminated water using the novel PVP-assisted AlNiMn nanocomposite. The results from experiments showed that the novel polymer assisted nanocomposite adsorbed over 3000 mg/L sulfate ions from the model wastewater with an initial concentration of 5000 mg/L at optimal treatment conditions (of 150 rpm, pH 6, and 60 min contact time). The Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models were plotted to explain the adsorption isotherm equilibrium. The isotherm models suggest the sulfate adsorption followed the physical sorption mechanism. The experimental results had good fits (R² ≥ 99.5%) with both pseudo-first-order and pseudo-second-order. The polymer-stabilized metallic nanocomposite was proven to have an impressive adsorption capacity for sulfate ions in sulfate-rich wastewaters compared to other previously reported studies. This makes the PVP-AlNiMn nanocomposite to be potentially useful for the pre-treatment of sulfate-rich wastewaters.