This research used raw kaolinite (RK), thermally activated Kaolinite (TAK), hydroxyiron (iii) kaolinitecomposite (HKC), as adsorbent for the adsorption of phenol and cadmium from aqueous solutions over a concentration range of 5-25 mg/l and 10-50 mg/l respectively. Effect of initial pH on the adsorbates was carried out at pH 2-11 at (298 K), and adsorbent dosage from 0.5-2.5 g with 50 ml adsorbate solution. Adsorption thermodynamics were developed for 25-55°C for 5-25 mg/L and 10-50 mg/L of phenol and cadmium solutions for 1 hr for all the adsorbents. The Physicochemical characteristics of RK, TAK and HKC were shown to be:

Analysis of soil around the vicinity of Arufu mine field was conducted in order to ascertain the impact of mining on the environment. Concentrations of trace metals associated with Pb – Zn – barite mineralization were determine in soils using atomic absorption spectrophotometer (AAS) Varian AA 240, after acid digestion with a mixture of 1:1 hydrofluoric acid and aqua regia. Mean concentrations (µg/g) of metals ranged from 5.72 (As) – 451.44 (Pb) in dry season and 1.32 (Cd) – 504.61 (Pb) in wet season. Index of geoaccumulation were in the following order of increasing magnitude: Cu < Zn < As < Pb < Ag for dry season and Cu < As < Zn < Cd < Pb for wet season. On the other hand, soil enrichment ratio ranged from Cu (1.06) – Ag (126.18) and Cu (1.35) – Pb (34.10) in dry and wet season respectively. Levels of metals measured were higher than their corresponding values reported for soil in the upper continental crusts. Toxic metal (Pb) has its mean concentration above maximum tolerance level while Zn and As levels were below the maximum tolerable levels. The presence of Pb above maximum tolerance level may render the soil unsuitable for agricultural practices, hence high impacts of Pb – Zn mining in the study area.

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This study is aimed at the preliminary investigation of microplastics as carrier of heavy metals pollution in surface sediment. Heavy metals concentration was determined by FAAS while microplastics characterization was analysed by ATR-FTIR spectrophotometer. The results obtained showed high level of lead (Pb) concentrations which ranged from 21.37 - 32.80 mg/kg across the sampling sites while Cd has the least concentration between 0.04 - 0.80 mg/kg. The concentration of Pb and Cd were above the USEPA permissible limit in sediment. The following absorption bands; 2978.19, 1728.28 and 1458.23 cm-1 with the functional groups; C-H stretch, C=O stretch and CH2 bend indicates the presence of Ethylene vinyl acetate (EVA) in site S2 and S4 respectively. Other microplastics found in the sampling sites are Nylon, Nitrile, Polycarbonate and Poly propylene. This indicates that there is identical distribution of the microplastics in the sampling sites. The quantities of microplastics isolated ranged from 8.11 - 8.16 g across the sites. Aquatic organisms fed on these polymeric materials because of their unique appearance. Hence, heavy metals adsorption will lead to higher concentrations on microplastics which could be ingested and lead serious complication in their intestine.

This study quantified and assessed the mobility of iron, nickel, cobalt and lead in soils around a sack and packaging company using indices such as mobility factor and risk assessment code. The results evaluating the mobility factor of heavy metals in soils around the sack and packaging company reveal that all the metals determined exceed the minimum limit of 10% mobility factor and are mobile with the mobility factor being in the order of: Ni > Pb > Co > Fe in the test soil. The risk assessment of heavy metals in the area based on risk assessment code ranged from low risk to medium risk (1-30%) where the risk level of the heavy metals is in the order:  Co > Ni > Pb > Fe in the test soil.