Sorption of Cu and Zn was investigated using single and mixed mineral systems under sulfidic-anoxic condition to treat wastewater obtained from disused mine pits at Parys Mountain in, United Kingdom. Water courses are the recipients of these contaminants. In these water courses fishing activities exist. Attempt was made to reduce the Cu and Zn levels intake in the watercourses using mineral systems of clays and goethite. These were tested with the mine waste water for characterization of copper and zinc removal at variable pH, solid concentration and contact time. In addition, levels of saturation of hydroxyl complexes were modeled. Batch reactions conducted at ambient temperature (23±2°C) reveal all systems of assorted minerals sorbed more Cu than Zn. In addition, Cu sorbed on iron sulfide exhibited increase in sorption with increasing pH. There was cross cutting effect of Cu and Zn sorbed on iron sulfide at pH 6 and Cu sorbed on goethite at about pH 7, These indicate similar metal removal characteristics. Differences in removal of copper and zinc ions may be assigned to outer sphere complexation and specific adsorption of copper and zinc ions. Non-promotive Cp effect (i.e. decrease in metal removal with increase in concentration of particle) was observed in all minerals. This effect may be assigned to increase in aggregation of the mineral particle size. Ageing characterization progresses as residence time was increased. This may be assigned thiol (=S-H) and hydroxyl (=Me-OH) groups and sites of reactions. There is no link to stable hydroxylation of copper and zinc species that could significantly contribute to the removal of these metals.

Two forms of activated carbon (i.e., granular and powdered forms) used to test mercury removal in solution. These activated carbons were obtained from the shells of a palmae biomass and used in mercury ion removal in aquatic systems. The African palmae shell taken out from a broadly and simply full-fledged palm tree. This biomass serves as a precursor in the formulation of activated carbons not documented. The powdered and granular fractions of activated carbons described for chemical composition, isoelectric point, and surface area. The mechanism of reactions and the kinetics involved were studied using the results of protonation and rate limitations. The parameters used in the batch mode study included pH, contact time, initial concentration of the adsorbate and the dose of the activated carbons. A comparison of performances, contact time demonstrated the highest adsorption efficiency of 93% for the powdered activated carbon and 92% for the granular activated carbon. The dosage recorded the lowest adsorption efficiency of 84% using granular activated carbon. Comparatively, this study brought to the fore that activated carbon derived from the Plamae biomass remains a novel bio-sorbent

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The removal of Lead (Pb 2+) ions from waste water in the aquatic environment by copper oxide-kaolinite composite forms an important step involved in the reduction of Lead ions in the environment. The study investigated the synthesis, characterization, and application of copper oxide-kaolinite composite in the removal of Lead ions from aqueous systems. The synthesis of the composite involved a trimetric process to produce the copper oxide (CuO)-kaolinite composite. The characterization involved the determination of cation exchange capacity, specific surface area, and spectral analysis by sodium saturation method, nitrogen gas adsorption techniques, and scanning electron spectroscopy, respectively. The determination of parameters affecting the reaction mechanism and reaction kinetics involved the use of batch mode techniques. The findings indicated a reaction mechanism that was less than one proton coefficient, higher mass transfer rates when compared with uncoated kaolinite. Here, the intraparticle diffusion was higher than the value for the uncoated kaolinite. The reactions based on Pb 2+ initial concentration indicated that the coated kaolinite gradually became saturated as the concentration was increased. The reactions based on solid concentration (Cp) demonstrated a complex change in the capacity of adsorption over different Pb 2+ concentrations (10-40 mgL −1) and solid concentrations (2-10 gL −1). Here, the reduction in specific surface area, particle size increase, mineral aggregation, and concentration gradient effect controlled the complex changes in adsorption. In conclusion, the copper oxide-kaolinite composite significantly enhanced the adsorption of Pb 2+ ions.

This paper has investigated the synthesis and characterization of CuO-coated goethite and its application in the removal of mercury. The presence of CuO coating significantly modified the adsorption pattern of mercury on goethite. The synthesis was carried out in a trimetric manner and characterization was conducted using standard laboratory procedures. Batch mode technique under reducing conditions at ambient temperature was used to determine mercury adsorption on CuO-coated goethite. Reaction mechanism indicated a less than one proton coefficient (0.68), an intraparticle diffusion that was controlled by boundary layer, an intercept C equals to 444.45, =0 and mass transfer rates (8.752 -6 cm h -1 and 7.216 -7 cm h -1 ) higher than those of previous studies. ARTICLE HISTORY

Iron oxides are chemical complexes which occur naturally, comprising iron and oxygen. Here, together, 16 types of iron oxides and oxyhydroxides have been identified. These two components of oxides are widely spread naturally. They are vital to humans and useful in most geological and biological activities. In addition, they are useful as pigments and catalyst in industries and hemoglobin in blood circulation. The interplay and conversion of these components from one form to another are essentially controlled by bacterial species. These contain 70 and 72% iron, respectively. Furthermore, iron ores are classified in terms of occurrence. Banded iron formation (BIF) comprises 15% iron, comprising minerals of iron that are bedded besides silica. Beneficiation processes of iron ore generate dust in the atmosphere, acid mine drainage in the ecosystem and metallic iron for steelmaking. Beneficiation process requires dissolution of minerals surrounding the ore and the release of metals and cement matrix into water courses. These generates acid leading to acid mine drainage. Therefore, there is a need for impact assessment of the environment in the planned beneficiation cycle. Sustainable beneficiation must be done to reduce impact on the natural, social or economic environment.

This work investigated the bulk geochemistry of fifteen (15) samples of Delta Steel Company (DSC) dump slag produced by the direct reduction steelmaking process, using the X–ray fluorescence spectroscopy (XRF) method and glass discs prepared from each of the fifteen test slag samples. The results indicate the presence of major amounts of CaO(36.62%), MgO(9.77%), Fe2O3(27.32%), SiO2(19.86%), Al2O3(5.43%), low amounts of MnO(1.46%), TiO2(0.42%), Cr2O3(0.17%), P2O5 (0.53), and minor amounts of SO3(0.04). The geochemical composition of the slag indicates suitable use as iron making blastfurnace feed and as fertilizer. The low amount of MnO in the slag is advantageous as it can reduce the disadvantage of probably causing refractory lining destruction in the presence of a notable amount of K20. The use of this slag would contribute to the conservation of natural steelmaking resources, improved crop yeild and reduction in CO2 emission in the company environment.