Capturing Cd2+ ions from wastewater using PVA/α-MnO2–oleic acid nanocomposites

Abstract

In the present study, poly(vinyl alcohol) nanocomposites (PVA NCs) filled with modified α-MnO₂ nanorods (NRs) were fabricated through the sonochemical method, which is a fast, economical, and eco-friendly method. In order to uniformly disperse the α-MnO₂ NRs in the PVA matrix, the α-MnO₂ NRs were modified with oleic acid (OA). The amount of OA grafted onto the α-MnO₂ surface was found to be about 13 wt% by thermogravimetric analysis. The PVA/α-MnO₂–OA NCs were characterized and their morphology, thermal, mechanical, and water treatment behaviors were studied. The results showed a positive influence of α-MnO₂–OA on the thermal stability and mechanical resistance of the NCs. Also, the outcomes demonstrated that the PVA/α-MnO₂–OA NCs can be promising adsorbents for the efficient uptake of Cd²⁺ ions from aqueous solution. The adsorption isotherms were studied by applying the Langmuir and Freundlich models, and the Freundlich model showed better agreement with the experimental data. The adsorption kinetics investigation demonstrated that a pseudo-second-order model was more suitable for the adsorption process.