Abstract: The gold extraction process by mercury amalgamation is recognized worldwide as a process presenting an environmental and health risk linked to mercury contamination of the geo and biosphere close to the gold panning site. The aim of this work is to assess the risk of contamination by mercury of populations living in the locality of Bétaré-oya, which is subject to the phenomenon of small-scale artisanal mining. In order to achieve this, a small social survey was carried out on two gold extraction sites in the locality of Bétaré-oya. Samples of sediment, water and fish were also taken from these sites. After characterization, these samples underwent the total mercury was determined by an automatic mercury analyzer. Moreover, the methyl mercury was extracted from the samples and analyzed by inductively coupled plasma mass spectrometer coupled to gas chromatography and by gas chromatography coupled to an electron capture detector. The results obtained showed total mercury concentrations varying from 386 to 5072 µg/kg in sediments and from 24.6 to 8451 ng/L in water. Methyl mercury was measured at concentrations ranging from 7.62 to 165 µg/kg in sediments, from 2.54 to 15 µg/L and from 45.4 to 90.8 µg/kg in fish. Well water (15.0 ± 2.4 µg/L of methyl mercury) which is consumed by the populations of the study site, and fish contaminated with an average concentration of 68 µg/kg of Methyl mercury, represent the main vectors of the risk of direct contamination of the populations of the locality of Bétaré-oya by this pollutant.
Abstract: The gold extraction process by mercury amalgamation is recognized worldwide as a process presenting an environmental and health risk linked to mercury contamination of the geo and biosphere close to the gold panning site. The aim of this work is to assess the risk of contamination by mercury of populations living in the locality of Bétaré-oya, whic...Show More
Abstract: The presence of heavy metals in water is one of the major environmental issues. In this study, desert date seed shells were employed as precursors for the production of activated carbon by chemical activation process using phosphoric acid (DDSSA) and potassium hydroxide (DDSSS). The activated carbon derived desert date seed were characterized using XRD, FTIR, Raman spectroscopy, SEM analysis and point of zero charge. The most significant variables that affect the adsorption of iron ions, including pH, contact time, and initial concentration, have been investigated. The results of the research were successfully assessed by Langmuir model. Interestingly, the maximum adsorption ability of Fe2+ was found to be 132.25 mg/g onto DDSSA and 126.35 mg/g onto DDSSS, this was found to be higher in comparison to the similar activated carbon obtained by other researchers. The pseudo 2nd order model was also utilized to describe the adsorption and the data showed that adsorption kinetic of Fe2+ ions onto the DDSSA and DDSSS is dominated by chemisorption. Moreover, thermodynamic parameters suggested that DDSSA and DDSSS for Fe (II) adsorption phenomenon were endothermic and spontaneous. Taken together the high availability, facile production along with high performance of activated carbon from desert date seed shells make it an economically adsorbent for Fe (II) adsorption.
Abstract: The presence of heavy metals in water is one of the major environmental issues. In this study, desert date seed shells were employed as precursors for the production of activated carbon by chemical activation process using phosphoric acid (DDSSA) and potassium hydroxide (DDSSS). The activated carbon derived desert date seed were characterized using...Show More