Recycling of Steel Industry Waste Acid in the Preparation of Fe3O4 Nanocomposite for Heavy Metals Remediation from Wastewater

This study was steered to convert waste acid ensued from the pickling process in steel industries to an esteemed nanocomposite for the elimination of heavy metals (HMs) from wastewater. Magnetic nanoparticles (Fe3O4) preparation from waste was performed by the co-precipitation method. These magnetic nanoparticles are modified by carboxymethyl-a-cyclodextrin polymer (CM-a-CD) through copolymerization reactions. The data obtained from FTIR, XRD, and TEM point up that CM-a-CD is entrenched onto Fe3O4 nanoparticles. The generated CM-a-CD / Fe3O4 was employed for HMs deportation from contaminated water and the adsorption results revealed that CM-a-CD/ Fe3O4 sorption efficiency was in the order of Pb(II) ] Cd(II) ] Cr(VI). The highest adsorption capacity was 64.2 (mg/g) for Pb(II). The kinetic study revealed that the HMs sorption by CM-a-CD/ Fe3O4 follows the pseudo-second-order model. The equilibrium modeling study proved that the Langmuir isotherm model was more fitting. The coexisting ions do not significantly alter the percentage removal of the measured metal ions. The efficiency of the synthesized polymer is particularly high in the tested field samples. Thus, CM-a-CD/ Fe3O4 has an extremely high adsorption capability in the field application as well as excellent reusability results, which will reduce the cost for the CM-a-CD / Fe3O4 as an adsorbent for wastewater treatment.