Removal of heavy metals from industrial wastewater using natural and organically modified minerals

• Vermiculite & zeolite: cost-effective for heavy metal wastewater treatment. • Natural & modified minerals can purify wastewater to meet environmental standards. • Vermiculite most effective at removing pollutants. • Chromium & lead removal meets environmental standards, but lead for subsoil only. The reuse of industrial or municipal wastewater for irrigation is increasingly common due to its availability and the pressing need for effective disposal methods. However, this practice elevates heavy metal concentrations in water and soil. This study investigates the removal of heavy metals from industrial wastewater from the petroleum industry through an adsorption process using natural and organically modified minerals. Petroleum wastewater samples were charged with Cr(III), Cr(VI), Cu(II), Mn(II), Ni(II), Cd(II), Pb(II), and Zn(II) ions at 10 mg/L concentration levels. The efficiency of adsorption by natural and modified zeolite and vermiculite was evaluated using adsorbent concentrations of 10 g/L with a pH of 4. Overall, the experimental results showed that vermiculite was more effective in removing pollutants from the wastewater. Lead and chromium removals using vermiculite were shown to be greater than 99% according to Atomic Absorption Spectrometry (AAS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Statistical evaluations have shown that the efficiency at which vermiculite removes pollutants is influenced by the mineral content, adsorption capacity, and percentage of removal. Similarly, zeolite's effectiveness depends on its adsorption capacity and rate of removal. The results indicate that both natural and organically modified minerals are effective in purifying industrial wastewater containing heavy metals, achieving removal rates that meet environmental standards. Thus, this study highlights the potential of using vermiculite and zeolite as cost-effective and efficient solutions for treating heavy metal-laden industrial wastewater, offering a promising approach to mitigating the environmental and public health risks associated with heavy metal contamination.