The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Bhekie B. Mamba - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of charcoal ash nanoparticles pollutant removal capacity from Acid Mine Drainage rich in iron and sulfate
Journal of Cleaner Production, 2020Co-Authors: Kebede K. Kefeni, Bhekie B. MambaAbstract:Abstract Acid Mine Drainage is globally recognized as one of the environmental pollutants, due to its highly toxic metals and sulfate concentration. In this study, the effect of metal and sulfate removal capacity of Namibian hardwood charcoal ash from Acid Mine Drainage was investigated. The experimental results have shown that charcoal ash has dual pollutant removal capacity via adsorption and precipitation. For adsorption, insoluble charcoal ash Minerals and precipitates produced during treatment are responsible. While soluble metal oxides and sparingly soluble carbonates are essential for neutralization of the Acid Mine Drainage and metal hydroxide precipitation. Based on the treated Acid Mine Drainage analysis results, almost complete and partial removal of toxic metals and sulfate from Acid Mine Drainage was observed, respectively. Unlike commonly used lime or limestone obtained by purchasing and also which requires crushing to form a powder, charcoal ash obtained for free, need no modification due to its nanoparticle size (20–96 nm) and environmentally friendly nanomaterials. Collection and use of charcoal ash for pollution remediation is one way of creating a clean environment. Overall, charcoal ash performed well in metals and sulfate removal and has been found an attractive and novel-alternative for Acid Mine Drainage treatment, with an added-value of resource recovery.
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Synthesis and application of hematite nanoparticles for Acid Mine Drainage treatment.
Journal of Environmental Chemical Engineering, 2018Co-Authors: Kebede K. Kefeni, Titus A.m. Msagati, Thabo T.i. Nkambule, Bhekie B. MambaAbstract:Abstract In this paper, the synthesis of pure hematite nanoparticles, magnetic properties and its removal capacity of metal cations from Acid Mine Drainage are well described. Initially, mixtures of iron oxide nanoparticles were synthesised using hydrated ferric chloride and ferrous sulphate salt solution by co-precipitation method and converted to hematite via calcination at 500 °C. The synthesised hematite nanoparticles have shown superparamagnetic character with saturation magnetisation of 5.6 emu g−1. Treatment of partially aerated Acid Mine Drainage in the presence of 0.85 g L−1 of synthesised hematite resulted in complete removal of Al, Mg, Mn and Fe while for Zn and Ni over 80% and Ca and Na in between 47 and 72% removals. The sludge generated from the treated Acid Mine Drainage was also characterised by relevant analytical instruments. Overall, the non-toxicity, stability and high metal removal capacity of hematite nanoparticles is promising for the future application in large-scale Acid Mine Drainage treatment.
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Acid Mine Drainage prevention treatment options and resource recovery a review
Journal of Cleaner Production, 2017Co-Authors: Kebede K. Kefeni, Titus A.m. Msagati, Bhekie B. MambaAbstract:Acid Mine Drainage poses severe environmental pollution problems due to its high Acidity, toxic metals and sulphate contents. In this review, the available prevention of Acid Mine Drainage generation, treatment options and their importance in light of the future perspectives are briefly discussed. The possible resources to be recovered such as ferric hydroxide, ferrite, rare earth metals, sulphur and sulphuric Acid and their economic benefit are discussed. Furthermore, the importance of Mine tailing for stabilisation of contaminated soil and production of building materials are highlighted. Overall, this review has shown that the resource recovery and reuse is a non-debatable holistic approach to environmental sustainability and Acid Mine Drainage pollution reduction. Finally, the future perspective and areas that deserve in-depth exploration are underscored.
Kebede K. Kefeni - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of charcoal ash nanoparticles pollutant removal capacity from Acid Mine Drainage rich in iron and sulfate
Journal of Cleaner Production, 2020Co-Authors: Kebede K. Kefeni, Bhekie B. MambaAbstract:Abstract Acid Mine Drainage is globally recognized as one of the environmental pollutants, due to its highly toxic metals and sulfate concentration. In this study, the effect of metal and sulfate removal capacity of Namibian hardwood charcoal ash from Acid Mine Drainage was investigated. The experimental results have shown that charcoal ash has dual pollutant removal capacity via adsorption and precipitation. For adsorption, insoluble charcoal ash Minerals and precipitates produced during treatment are responsible. While soluble metal oxides and sparingly soluble carbonates are essential for neutralization of the Acid Mine Drainage and metal hydroxide precipitation. Based on the treated Acid Mine Drainage analysis results, almost complete and partial removal of toxic metals and sulfate from Acid Mine Drainage was observed, respectively. Unlike commonly used lime or limestone obtained by purchasing and also which requires crushing to form a powder, charcoal ash obtained for free, need no modification due to its nanoparticle size (20–96 nm) and environmentally friendly nanomaterials. Collection and use of charcoal ash for pollution remediation is one way of creating a clean environment. Overall, charcoal ash performed well in metals and sulfate removal and has been found an attractive and novel-alternative for Acid Mine Drainage treatment, with an added-value of resource recovery.
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Synthesis and application of hematite nanoparticles for Acid Mine Drainage treatment.
Journal of Environmental Chemical Engineering, 2018Co-Authors: Kebede K. Kefeni, Titus A.m. Msagati, Thabo T.i. Nkambule, Bhekie B. MambaAbstract:Abstract In this paper, the synthesis of pure hematite nanoparticles, magnetic properties and its removal capacity of metal cations from Acid Mine Drainage are well described. Initially, mixtures of iron oxide nanoparticles were synthesised using hydrated ferric chloride and ferrous sulphate salt solution by co-precipitation method and converted to hematite via calcination at 500 °C. The synthesised hematite nanoparticles have shown superparamagnetic character with saturation magnetisation of 5.6 emu g−1. Treatment of partially aerated Acid Mine Drainage in the presence of 0.85 g L−1 of synthesised hematite resulted in complete removal of Al, Mg, Mn and Fe while for Zn and Ni over 80% and Ca and Na in between 47 and 72% removals. The sludge generated from the treated Acid Mine Drainage was also characterised by relevant analytical instruments. Overall, the non-toxicity, stability and high metal removal capacity of hematite nanoparticles is promising for the future application in large-scale Acid Mine Drainage treatment.
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Acid Mine Drainage prevention treatment options and resource recovery a review
Journal of Cleaner Production, 2017Co-Authors: Kebede K. Kefeni, Titus A.m. Msagati, Bhekie B. MambaAbstract:Acid Mine Drainage poses severe environmental pollution problems due to its high Acidity, toxic metals and sulphate contents. In this review, the available prevention of Acid Mine Drainage generation, treatment options and their importance in light of the future perspectives are briefly discussed. The possible resources to be recovered such as ferric hydroxide, ferrite, rare earth metals, sulphur and sulphuric Acid and their economic benefit are discussed. Furthermore, the importance of Mine tailing for stabilisation of contaminated soil and production of building materials are highlighted. Overall, this review has shown that the resource recovery and reuse is a non-debatable holistic approach to environmental sustainability and Acid Mine Drainage pollution reduction. Finally, the future perspective and areas that deserve in-depth exploration are underscored.
Travis W Tucker - One of the best experts on this subject based on the ideXlab platform.
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removal of phosphorus from agricultural wastewaters using adsorption media prepared from Acid Mine Drainage sludge
Water Research, 2009Co-Authors: Philip L Sibrell, Gary A Montgomery, Kelsey L Ritenour, Travis W TuckerAbstract:Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid Mine Drainage sludge is a waste product produced by the neutralization of Acid Mine Drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the removal of phosphorus. In this paper, we describe a method for the drying and pelletization of Acid Mine Drainage sludge that results in a particulate media, which we have termed Ferroxysorb, for the removal of phosphorus from wastewater in an efficient packed bed contactor. Adsorption capacities are high, and kinetics rapid, such that a contact time of less than 5 min is sufficient for removal of 60-90% of the phosphorus, depending on the feed concentration and time in service. In addition, the adsorption capacity of the Ferroxysorb media was increased dramatically by using two columns in an alternating sequence so that each sludge bed receives alternating rest and adsorption cycles. A stripping procedure based on treatment with dilute sodium hydroxide was also developed that allows for recovery of the P from the media, with the possibility of generating a marketable fertilizer product. These results indicate that Acid Mine Drainage sludges -- hitherto thought of as undesirable wastes -- can be used to remove phosphorus from wastewater, thus offsetting a portion of Acid Mine Drainage treatment costs while at the same time improving water quality in sensitive watersheds.
Titus A.m. Msagati - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and application of hematite nanoparticles for Acid Mine Drainage treatment.
Journal of Environmental Chemical Engineering, 2018Co-Authors: Kebede K. Kefeni, Titus A.m. Msagati, Thabo T.i. Nkambule, Bhekie B. MambaAbstract:Abstract In this paper, the synthesis of pure hematite nanoparticles, magnetic properties and its removal capacity of metal cations from Acid Mine Drainage are well described. Initially, mixtures of iron oxide nanoparticles were synthesised using hydrated ferric chloride and ferrous sulphate salt solution by co-precipitation method and converted to hematite via calcination at 500 °C. The synthesised hematite nanoparticles have shown superparamagnetic character with saturation magnetisation of 5.6 emu g−1. Treatment of partially aerated Acid Mine Drainage in the presence of 0.85 g L−1 of synthesised hematite resulted in complete removal of Al, Mg, Mn and Fe while for Zn and Ni over 80% and Ca and Na in between 47 and 72% removals. The sludge generated from the treated Acid Mine Drainage was also characterised by relevant analytical instruments. Overall, the non-toxicity, stability and high metal removal capacity of hematite nanoparticles is promising for the future application in large-scale Acid Mine Drainage treatment.
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Acid Mine Drainage prevention treatment options and resource recovery a review
Journal of Cleaner Production, 2017Co-Authors: Kebede K. Kefeni, Titus A.m. Msagati, Bhekie B. MambaAbstract:Acid Mine Drainage poses severe environmental pollution problems due to its high Acidity, toxic metals and sulphate contents. In this review, the available prevention of Acid Mine Drainage generation, treatment options and their importance in light of the future perspectives are briefly discussed. The possible resources to be recovered such as ferric hydroxide, ferrite, rare earth metals, sulphur and sulphuric Acid and their economic benefit are discussed. Furthermore, the importance of Mine tailing for stabilisation of contaminated soil and production of building materials are highlighted. Overall, this review has shown that the resource recovery and reuse is a non-debatable holistic approach to environmental sustainability and Acid Mine Drainage pollution reduction. Finally, the future perspective and areas that deserve in-depth exploration are underscored.
Maria Clara Costa - One of the best experts on this subject based on the ideXlab platform.
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Prokaryotic diversity in stream sediments affected by Acid Mine Drainage
Extremophiles, 2020Co-Authors: Jorge D. Carlier, Sara Ettamimi, Cymon J. Cox, Khalil Hammani, Hassan Ghazal, Maria Clara CostaAbstract:The microbial communities in mining impacted areas rely on a variety of mechanisms to survive in such extreme environments. In this work, a meta-taxonomic approach using 16S rRNA gene sequences was used to investigate the prokaryotic diversity of sediment samples from water bodies affected by Acid Mine Drainage at the São Domingos mining area in the south of Portugal. Samples were collected in summer and winter from the most contaminated sites from where the water flows downstream to the freshwater of Chança’s river reservoir. The prokaryotic diversity on water bodies’ sediments allowed us to distinguish the highly contaminated sites (pH ≈ 2) from sites with intermediate levels of contamination (pH ≈ 3–6.5), and from sites without contamination (pH ≈ 7.5). The abundances of Acidophiles of genera Acidiphilium, Acidibacter, Acidobacterium and Acidocella in the sediments were correlated with the level of Acid Mine Drainage contamination. The two first genera were among the 30 most abundant prokaryotes in all contaminated samples, including one (SS2w), where the contamination was very diluted, thereby emphasizing the impact that such type of pollution can have in the microbial communities of sediments. In addition, the high abundances of archaeal taxa from class Thermoplasmata and of bacteria from family RCP1-48 in the sediments from the most contaminated site corroborate their importance in such ecosystems and a putative role in the generation of Acid Mine Drainage.
