To this end, the Pb-extract from e-waste materials was converted to lead(II) oxide (PbO), which is recyclable to the industry for production of lead acid battery and as a drier in paint products. Since no amount of poison is safe, the identified e-waste toxic chemical components need to be managed. When compared with the literature toxicity and lethality values, the acute toxicity value for lead pointed to environmental health significance that called for intervention, while the acute toxicity value for beryllium oxide did not. The acute toxicity of the crude Pb-extract from e-waste materials was 400 mg kg-1, while that of crude BeO-extract was 1,600 mg kg-1. Pb can also be recovered by solvent-extraction technique. Both toxic components can be extracted mechanically from, and by chemical reactions with, e-waste materials. Furthemore, the study established their recyclability by mechmical, chemical and solvent-extraction techniques.įindings showed that lead (Pb) and beryllium oxide (BeO) are the hazardous chemical components occurring in environmentally significant quantities in e-waste materials. This book is a report on the work that sought to identify the toxic chemical components that occur in environmentally significant quantities in e-waste materials, and to establish their environmental health significance by determining their acute toxicity (rat, oral). Hence, the Aningene clay should be used in production of emulsion paint and Nwangene clay should be used in the production of harsh paints. The Aningene clay formulated paint gave better paint property than the Nwangene clay formulated paint. Also, none of the clay formulated paints chalked on drying. The performance tests showed that the opacity and spread rate of the clay formulated paints were lower than calcium carbonate formulated paint. While the viscosities were also higher than that of the calcium trioxocarbonate (IV) formulated paint.
The physical tests showed that the pH and specific gravities of the clay formulated paint were lower than that of the calcium trioxocarbonate (IV) formulated paint. The SEM micrograph of the calcined clays showed that the clay particles are 50 um in size. The Aningene clay also contained 6.08% of iron oxide (Fe2O3), the rest of the constituents is in small quantities for both clays. The XRF showed that the Aningene clay and Nwangene clay contained silica (SiO2) and aluminum oxide (Al2O3) percentages of 43.02%, 66.20% and 23.92%, 27.50% respectively. The compositional and morphological analyses were also carried out on the calcined clays via X-ray fluorescence and scanning electron microscopy. Physical and performance properties of the produced paint were determined. The calcined and uncalcined clay were used to formulate emulsion paint. The clay particles obtained were calcined at 750☌. The clay samples were prepared by washing, sedimentation, drying, grinding and sieving. This work investigated the pigment-extender effect of Aningene clay, Nwangene clay and calcium trioxocarbonate(iv) in emulsion paint. Local raw materials such as activated carbon, coal, rice husk, saw dust and clay should be employed in the treatment of the effluent as they are readily available and cost-saving. It is therefore recommended that adequate monitoring should be done through aggressive supervision on effluent treatment before discharge. This indicates that the effluent was discharged without proper treatment. The values of the mean concentrations of the elements Pb, As, Cd, Cr, Ca, Zn, Na, Hg, Fe and Co in both the soil and effluent samples showed excessive levels above the recommended standards for WHO and NESREA with the exception of Na, Ca and Zn.
The soil samples were digested using aqua regia for the elemental analysis for the detection of ten different metals (lead, arsenic, cadmium, chromium, calcium, zinc, sodium, mercury, iron and cobalt) using atomic absorption spectrophotometer. The soil samples were sourced 2-metres distance away from the discharge point of the effluent. The elemental analysis of soil and effluent samples were conducted. This research paper investigates the heavy metal content of the effluent and soil samples in order to determine the level of toxicity and pollution by the metals to the environment.
Some heavy metals contained in these effluents from the industry have been found to be carcinogenic, toxic or poisonous to the environment (plants, animals and humans). Industrial pollution by effluents is one of the major problems facing Nigerians at present and several efforts are being vigorously engaged to control it in the various industry spanning the length and breadth of the country to see that Nigerians live in a disease-free environment.
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