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The purpose of this study is to investigate the effectiveness of banana peel activated carbon as an adsorbent in the removal of cyanide and selected metals from fresh cassava wastewater collected from the discharge pit. Fresh banana peels were dried, adequately prepared and treated with 0.1 M HCl. Batch experiments were conducted by varying the adsorbent dose from 5 -20 g and contact time between 10 -360 minutes to determine the optimum percentage removal of cyanide -CN and selected metals (lead -Pb, chromium -Cr and cadmium -Cd) from the wastewater. Adsorption percentage was found to be proportional to contact time and dosage. Maximum removal percentage of the cyanide and metals at pH 7.2 was 96.45%, 15 g adsorbent in 300 minutes for CN, 98%, 20 g adsorbent in 240 minutes for Pb, 98%, 20 g adsorbent in 180 minutes for Cd while with 5 g adsorbent, initial traces of Cr in the wastewater was no longer detected. The effectiveness of the Original Research Article

The city of Ilorin in Nigeria has experienced high population growth and rapid urbanization. Agba Dam is one of the major sources of potable water in Ilorin, and currently being threatened by anthropogenic induced encroachment activities, with potential for significant derogatory effects on its quality. Therefore, this paper assesses the qualitative impact of encroachment on the water resources regime of Agba Dam, Ilorin, Nigeria. Field survey was carried out to scope proximal anthropogenic activities and to delineate historical as well as current extent of the encroachment area of the dam. Representative water samples were collected from locations within the dam catchment, and subsequently analyzed for alkalinity, dissolved carbondioxide, chloride, total iron, copper, sulphate, colour, calcium, dissolved oxygen and turbidity. In addition, historical physical and chemical data of water samples obtained from the dam were also acquired, and analyzed to determine temporal variation in the quality. The results show a reduction of 0.89 km2 or 63% in the historical buffer boundary of the dam. The values of the measured physico-chemical parameters were generally similar to that obtained for the historical values and therefore suggest limited impact of the anthropogenic activities on the water quality. However, slight increases were observed in the measured concentrations of the alkalinity, dissolved carbondioxide, chloride, iron, copper and sulphate, and this indicates possibilities of water quality alteration, with potential consequences for ecosystem and aquatic life if the trend is unabated.

The menace of wastewater pollution in the 21st century is becoming alarming. Application of the low-cost adsorbents for wastewater treatment has received more attention this moment in environmental history than never. Most industrial wastewater has not been receiving adequate treatment prior to disposal into the nearby stream, and this is a potential threat to plants and animals feeding therefrom. There is therefore the need to proffer an effective solution to this pollution problem. An approach of bioremediation with a cost-effective plant waste is considered apt, with the application of Azadirachta indica (Neem tree) bark as adsorbent in this study. Galvanizing/wire-gauze industrial wastewater effluents were collected and subjected to Atomic Absorption Spectrophotometry (AAS) analysis to determine the concentrations of heavy metals. Phytochemical and Proximate analyses of the adsorbent were performed while adsorption study with the effects of adsorbent dosage, contact time, stirring speed and pH on the adsorption process during the wastewater treatment was carried out. The adsorption isotherms and kinetic models that best described the adsorption of Pb 4+ and Cr 3+ were established.

With the geometric population growth in developing nations comes increase in waste generation, these wastes ranging from industrial to agricultural to municipal solid waste calls for measure for its effective management and disposal so as to preserve the ecosystem. An effective measure of containing this large waste generated, is through the use of landfills which are designed and built to protect infiltration of leachates from decomposed waste to the groundwater. It is with this in mind, that this study seeks to assess the effect of bentonite (0 to 15%) on clayey soil as a base liner for landfills. In achieving this aim, two clayey samples gotten from a borrow site at a depth of 1.5 and 2.0m for samples A and B respectively were modified with bentonite. Particle size analysis, moisture-density relationship and permeability tests were performed on the test and the bentonite-modified samples in accordance with relevant standards. Result shows an increasing plasticity index, and liquid limit of both samples with increasing bentonite content. Permeability and dry densities of the samples decreases on bentonite modification. The application of bentonite modified the soil as it improves their plasticity and hydraulic properties. Bentonite modification made the clayey soil suitable for use as a liner material in landfills for municipal solid waste containment.