Sequestering of iron and lead from groundwater using chemically modified Cucumis melo rind

Abstract

Heavy metal contamination in groundwater is among the significant environmental issues which require high priority of remediation action due to its importance in our daily life. This study intended to upcycle Cucumis melo (C. melo) rind which a waste from agricultural industries as natural adsorbent to remove iron (Fe) and lead (Pb) ions from groundwater. The efficiency of C. melo rind to remove Fe and Pb under pre-determined optimum conditions were analyzed and the result showed that metal removal was up to 96.83 % for Fe and 94.88 % for Pb ions under Fe ion-optimized working conditions. While under Pb ion-optimized working conditions, the removal percentage obtained were up to 87.19 % for Fe and 95.09 % for Pb ion. Adsorption isotherm analysis data of both metal ions were fitted well to the Langmuir model with maximum adsorption capacity of 5.35 mg/g and 0.08 mg/g for Fe and Pb ions respectively. The kinetics experimental data correlated well with the pseudo-second order kinetics model. From the characterization study of the biosorbent using scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDX), X-ray fluorescent spectrophotometry (XRF) and Fourier transform infrared spectrometry (FTIR), ion exchange and micro precipitation were estimated to be the main mechanism governing the biosorption process by C. melo rind. The results demonstrated that C. melo rind has the potential to be developed as the adsorbent material for the removal of Fe and Pb ions from groundwater.