Supported nano zero-valent iron is receiving great attention nowadays due to its effectiveness in treating heavy metal pollutants. Therefore, this study aimed to investigate the effectiveness of granitic residual soil-supported nano zero-valent iron (Gr-nZVI) for the removal of the heavy metals Pb²⁺, Cu²⁺, Co²⁺, Cd²⁺ Ni²⁺ and Zn²⁺ in mixture solutions under different experimental conditions of batch equilibrium tests. In this study, Gr-nZVI was successfully synthesized by using the chemical reduction of Ferric Chloride Hexahydrate (FeCl₃.6H₂O) and Sodium Borohydride (NaBH₄)_. The physical and chemical properties, morphology and mineralogy of all adsorbents were characterized by the Braeuer–Emmett–Teller (BET) method, cation exchange capacity (CEC), X-ray fluorescence (XRF), scanning electron microscopy (SEM), field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Isotherm, kinetic and diffusion model analyses were conducted to fit the experimental data. The results show rapid adsorption within 5 min in the initial adsorption stage for Pb²⁺ on nZVI (q_e.Pb = 17.89 mg/g) and Gr-nZVI (q_e.Pb = 15.29 mg/g). nZVI and Gr-nZVI also showed no significant effects on pH and temperature, serving as a good example of an energy-efficient process. The isotherm data fitted better to the Langmuir model and the pseudo-second-order kinetic model for the adsorption of all of the heavy metals. The diffusion models revealed that adsorption was not the only rate-limiting step. In this study, nZVI compared to Gr-nZVI and Gr demonstrated superior adsorption capacity for the heavy metal adsorption selectivity. Hence, these materials can be utilized as alternative energy-efficient adsorbents for the adsorption of metal ions from wastewater.

Dyes used in textiles, foods, cosmetics, and chemicals have become a major environmental pollution issue around the world. To address this issue, a number of technologies have been created to remove these pollutants from the environment. Due to their superior properties at nanoscale, numerous nanomaterials have been applied to remove dyes from polluted waters. This research presents the findings of the development of bentonite nano zero-valent iron (B-nZVI) for the treatment of synthetic cationic dyes. This study has three objectives: (i) to produce bentonite nano zero-valence iron (B-nZVI), (ii) to characterize its adsorbents (B-nZVI), (iii) to characterize its adsorption capacity. Four main tests were used for this purpose: (i) a physical test (Brunauer–Emmett–Teller (BET) surface area), (ii) a chemical test (cation exchange capacity (CEC) and X-ray fluorescence (XRF)), (iii) morphology (field emission scanning electron microscopy (FESEM) and (iv) mineralogy (Fourier transform infrared spectroscopy (FTIR). The five factors for the batch equilibrium test are adsorbent dose, concentration, kinetic, pH, and temperature. The batch test showed that the optimum dose for all adsorbents is 0.5 g. For the concentration factor, B-nZVI exhibits larger adsorption capacity (K_L = 30,314.0536 L/g; R² = 1) compared to bentonite (K_d = 0.0219 L/g; R² = 0.8892). The kinetic factor showed that the adsorption capacity by pseudo-second-order model was the best for both adsorbents (q_e = 1.2038 mg/g, R² = 0.9993 for bentonite and q_e = 6.9979 mg/g, R² = 1 for B-nZVI). For B-nZVI, the interparticle diffusion model (K_f = 0.8645 m² g⁻¹ min L⁻¹; R² = 0.9) and intraparticle diffusion model (K_d = 2.3829 m² g⁻¹ min L⁻¹; R² = 0.9189) showed a good correlation with the adsorption data, while bentonite showed a lower correlation with the interparticle diffusion model (K_f = 0.0002 m² g⁻¹ min L⁻¹; R² = 0.6253) and intraparticle diffusion model (K_d = 0.2886 m² g⁻¹ min L⁻¹; R² = 0.6026), respectively. The pH factor showed that the adsorption capacity of bentonite (q_e = 0.5674 mg/g) and B-nZVI (q_e = 5.3284 mg/g) was highest in acidic conditions (pH 2). As for the temperature factor, there was no significant effect on bentonite and B-nZVI. Therefore, tests can be conducted at room temperature, saving energy. It was also concluded that B-nZVI is the best material for removing MB compared to bentonite and can be considered for the treatment materials of contaminated water.

Effective interpretation of provenance and tectonic settings that affected a sedimentary deposit was optimised using a geochemistry and mineralogical interdisciplinary approach. Geochemical data was integrated with petrographic data to interpret the provenance and tectonic history of some sedimentary samples selected from a sedimentary sequence exposed along Imiegba in southern Nigeria. Sixteen samples were subjected to X-ray Fluorescence (XRF) analysis to assess the essential oxide composition and eighteen were analysed for their rare earth element compositions. Ten sedimentary samples were prepared into thin sections for a mineralogical study under a petrographic microscope. The geochemical approach using the compositional plot of TiO₂, Al₂O₃, Fe₂O₃, MgO, CaO, Na₂O and K₂O of the samples on a discriminant function shows a Felsic igneous source which is confirmed by the enrichment in the light rare earth elements concentration. It also indicates intermediate and Quartzose sedimentary provenance on a passive margin and oceanic island arc. The modal composition of quartz, feldspar and rock fragments plotted on a triangular diagram indicate metamorphic, plutonic and recycled orogen provenances, with a cratonic interior, and continent transitional and basement uplift activities. The study area thus contains sedimentary deposits derived from plutonic, metamorphic, and quartzose sedimentary provenance with imprints of divergent tectonic and convergent tectonic activities.