Abstract:

Removal of harmful heavy metals from the environment is a priority amongst scientists globally. Sorption technique using agro-waste materials as adsorbents is considered an effective and eco-friendly procedure for environmental remediation. Therefore, Raw (RPF) and copper nano composite (CuPF) of palm fronds were used as adsorbents to remove lead (II) ion from aqueous solution. The effects of contact time, pH, dosage, temperature, and concentration on the adsorbents were investigated during the adsorption process. Atomic absorption spectrometry (AAS), scanning electron microscope (SEM), Fourier transform infrared spectrometry (FTIR), and X-ray diffractometry (XRD) were used to qualify and quantify the absorbate and the adsorbents. According to the results, the materials’ nature and shapes were crystalline and non-spherical, rough and waxy, as confirmed by XRD and SEM analysis. Fourier transformed infra- red spectrometry displayed the presence of OH, S-H, C=O functional groups. The results showed that in all conditions studied, that CuPF had higher adsorption capacities than the nano counterpart. Statistical analysis with a one-way ANOVA test showed that there is a significant difference in the mean efficiency of RPF and CuPF for all the conditions studied. Kinetic studies proved that the pseudo-second order model best fitted the data. The intercepts of the intraparticle diffusion models (162.48 and 180.6) for RPF and CuPF respectively, indicated that the sorption of lead onto RPF and CuPF is not only a surface reaction. Equilibrium studies showed that Langmuir isotherm model displayed the best fit for the adsorption data. The positive values of ΔHo and ΔSo indicate an endothermic process and an increase in the degree of disorderliness at the metal ions interface leading to an enhanced interaction and, in turn, higher lead ion adsorption. The negative values of ΔGo indicates the spontaneity of the process. Conclusively, palm fronds and their nano-modified counterpart could serve as a good alternative to conventional adsorbents used to treat industrial waste water effluent due to their availability, cheapness, efficacy, and eco- friendliness