The Experts below are selected from a list of 47577 Experts worldwide ranked by ideXlab platform
Bernhard K Keppler - One of the best experts on this subject based on the ideXlab platform.
-
Thioglycolate-based task-specific ionic liquids: Metal Extraction abilities vs acute algal toxicity
Journal of Hazardous Materials, 2017Co-Authors: Sonja Platzer, Raphlin Leyma, Sara Wolske, Regina Krachler, Franz Jirsa, Michael Schagerl, Esther Heid, Wolfgang Kandioller, Christian Schröder, Bernhard K KepplerAbstract:Abstract We studied the Extraction behavior of two thioglycolate-based ionic liquids (ILs), for heavy Metals from aqueous solutions; substances of interest were methyltrioctylammonium S -hexyl thioglycolate [N 1888 ][C 6 SAc] and methyltrioctylphosphonium S -hexyl thioglycolate [P 1888 ][C 6 SAc]. Theses ILs previously have shown very good Extraction abilities towards cadmium and copper, therefore we investigated time-dependent Metal removal experiments with aqueous solutions of cobalt(II), nickel(II) and zinc(II). The highest distribution ratio (R IL/Water ) was determined for zinc (R IL/Water = 2000). Recovery studies for zinc after Extraction were performed with different stripping agents showing a successful recycling. Additionally, the two ILs were immobilized on active charcoal, displaying great potential for solid-liquid Extraction. Regarding the Extraction mechanism, quantum-mechanical calculations were included, which indicate that the Metal Extraction depends on the stability of the Metal-water cluster. Ligands (water as well as ILs) are planar coordinated in nickel complexes but showed a tetrahedral configuration for zinc. As a first estimate of the ecotoxicity of the ILs, in vivo tests toward three freshwater green algae species Tetradesmus obliquus , Desmodesmus armatus and Raphidocelis subcapitata were carried out. The EC 50 values (effective concentration after 72 h) confirm high toxicity of all tested ILs to all species, displaying only small differences between the species and EC 50 ies.
-
Task-specific thioglycolate ionic liquids for heavy Metal Extraction: synthesis, Extraction efficacies and recycling properties
Journal of Hazardous Materials, 2017Co-Authors: Sonja Platzer, Raphlin Leyma, Regina Krachler, Franz Jirsa, Wolfgang Kandioller, Mega Kar, Sonia Chib, Alexander Roller, Douglas R. Macfarlane, Bernhard K KepplerAbstract:Eight novel task-specific ionic liquids (TSILs) based on the thioglycolate anion designed for heavy Metal Extraction have been prepared and characterized by 1H and 13C NMR, UV-Vis, infrared, ESI-MS, conductivity, viscosity, density and thermal properties. Evaluation of their time-resolved Extraction abilities towards cadmium(II) and copper(II) in aqueous solutions have been investigated where distribution ratios up to 1200 were observed. For elucidation of the IL Extraction mode, crystals were grown where Cd(II) was converted with an excess of S-butyl thioglycolate. It was found by X-ray diffraction analysis that cadmium is coordinated by five oxygen and one sulfur donor atoms provided by two thioglycolate molecules and one water molecule. Leaching behavior of the hydrophobic ionic liquids into aqueous systems was studied by TOC (total dissolved organic carbon) measurements. Additionally, the immobilization on polypropylene was elucidated and revealed slower Metal Extraction rates and similar leaching behavior. Finally, recovery processes for cadmium and copper after Extraction were performed and recyclability was successfully proven for both Metals.
A. B. Ade - One of the best experts on this subject based on the ideXlab platform.
-
Protein Profiling of Thiobacillus ferrooxidans and Pseudomonas fluorescens Mutants during Metal Extraction
Journal of Scientific Research, 2018Co-Authors: S. M. Shaikh, R. U. Shaikh, A. B. AdeAbstract:Proteins are specific for the specific task associated with the cell. The Metal extracting bacteria, Thiobacillus ferrooxidans and Pseudomonas fluorescens have two different mechanisms for the Metal Extraction. One extracts the Metals by donating electrons and by doing self-oxidation and another is accumulating the Metals onto its cell surface which is negatively charged. Therefore to differentiate the task of Metal Extraction protein profiling was done and compared. The water soluble proteins were analyzed through SDS-PAGE. There was no significant difference in the profiles of both.
-
Effect of pH on Metal Extraction From Bauxite Ore by Thiobacillus Ferrooxidans
Journal of Scientific Research, 2010Co-Authors: Z. S. Khan, S. M. Shaikh, A. B. AdeAbstract:The extremophile, Thiobacillus ferrooxidans was selected to study the effect of pH on Metal Extraction from bauxite ore. This bacterium was inoculated in 9K medium having different pH, along with the bauxite ore, as Metal source. After one month of incubation the Extraction of Metals aluminum and iron was measured by spectrophotometric methods. It was found that the Extraction of aluminum was found better as compare to iron from bauxite at pH 2. Keywords: Aluminum; iron; Metal Extraction; pH; Thiobacillus ferrooxidans . © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v2i2.4020 J. Sci. Res. 2 (2), 403-406 (2010)
Klaus Bosecker - One of the best experts on this subject based on the ideXlab platform.
-
bioleaching Metal solubilization by microorganisms
Fems Microbiology Reviews, 1997Co-Authors: Klaus BoseckerAbstract:Bioleaching is a simple and effective technology for Metal Extraction from low-grade ores and mineral concentrates. Metal recovery from sulfide minerals is based on the activity of chemolithotrophic bacteria, mainly Thiobacillus ferrooxidans and T. thiooxidans, which convert insoluble Metal sulfides into soluble Metal sulfates. Non-sulfide ores and minerals can be treated by heterotrophic bacteria and by fungi. In these cases Metal Extraction is due to the production of organic acids and chelating and complexing compounds excreted into the environment. At present bioleaching is used essentially for the recovery of copper, uranium and gold, and the main techniques employed are heap, dump and in situ leaching. Tank leaching is practised for the treatment of refractory gold ores. Bioleaching has also some potential for Metal recovery and detoxification of industrial waste products, sewage sludge and soil contaminated with heavy Metals.
Bishal Baniya - One of the best experts on this subject based on the ideXlab platform.
-
A theoretical study of the potential for Metal Extraction from the incinerated ashes residing in Swedish landfills
Environmental Technology, 2013Co-Authors: Bishal BaniyaAbstract:In Sweden, waste incineration has played a major role in sustainable waste management, as well as generating combined heat and electricity for many years. Incineration of combustible waste produces residues such as fly ash and bottom ash. The chemical composition of both ashes shows that they consist of bulk Metals and scarce Metals in significant quantity, in elemental form as well as in small Metal pieces, which remain unsorted from the incinerated residues. This shows the potential for Metal Extraction from the ashes, which are deposited in Swedish landfills. Thus with the aim of quantifying selected Metals (Al, Cu, Fe, Zn, Sb, Sn, Ni, Co, Mo, Ti and V), and assessing their flows and stocks in different deposits, this study has been carried out. Approximately 50% of grate plants and 30% of fluidized bed plant in Sweden were sampled for the study. The data collected from the sampled plants were the basis for the calculation of flow of ashes and Metals through all the plants. First of all, annual Metal f...
-
A theoretical study of the potential for Metal Extraction from the incinerated ashes residing in Swedish landfills.
Environmental technology, 2013Co-Authors: Bishal BaniyaAbstract:In Sweden, waste incineration has played a major role in sustainable waste management, as well as generating combined heat and electricity for many years. Incineration of combustible waste produces residues such as fly ash and bottom ash. The chemical composition of both ashes shows that they consist of bulk Metals and scarce Metals in significant quantity, in elemental form as well as in small Metal pieces, which remain unsorted from the incinerated residues. This shows the potential for Metal Extraction from the ashes, which are deposited in Swedish landfills. Thus with the aim of quantifying selected Metals (Al, Cu, Fe, Zn, Sb, Sn, Ni, Co, Mo, Ti and V), and assessing their flows and stocks in different deposits, this study has been carried out. Approximately 50% of grate plants and 30% of fluidized bed plant in Sweden were sampled for the study. The data collected from the sampled plants were the basis for the calculation of flow of ashes and Metals through all the plants. First of all, annual Metal flows for 1985-2010 were estimated, based on which accumulated stocks at different deposits were calculated.
Nilotpala Pradhan - One of the best experts on this subject based on the ideXlab platform.
-
Biomineral Processing: A Valid Eco-Friendly Alternative for Metal Extraction.
Research and Reviews: Journal of Microbiology and Biotechnology, 2014Co-Authors: Lala Behari Sukla, Jacintha Esther, Eep P, Nilotpala PradhanAbstract:Over the past few years, the applications of certain microorganisms have gained importance in the field of applied environmental microbiology. Amongst them, biomineral processing is such field that deals with Metal mining from ores, concentrates, industrial wastes, overburdens etc. under the impact of microorganisms and/or their metabolites. The most successful advancement of mineral biotechnology so far is on copper, uranium, nickel-cobalt and gold bearing ores. Treatment of mineral industry effluents by microorganisms, with incidental recovery of some Metal values constitutes an equally important area of biomineral processing. The most common method followed for leaching or Extraction of Metal values is through shake flask (a lab scale method) followed by bioreactors or percolation columns (a bench scale method) and finally to heap leaching (a pilot scale method). Bio-leaching of mono- and multiple-sulphides is now coming to be known as an established commercial process. The present review discusses the microorganisms involved in biomineral processing, mechanism of Metal Extraction, molecular methodologies adopted for microbial identification with our experience on application of microorganism.
-
RESEARCH AND REVIEWS: JOURNAL OF MICROBIOLOGY AND BIOTECHNOLOGY Biomineral Processing: A Valid Eco-Friendly Alternative for Metal Extraction.
2014Co-Authors: Lala Behari Sukla, Jacintha Esther, Sandeep K. Panda, Nilotpala PradhanAbstract:Over the past few years, the applications of certain microorganisms have gained importance in the field of applied environmental microbiology. Amongst them, biomineral processing is such field that deals with Metal mining from ores, concentrates, industrial wastes, overburdens etc. under the impact of microorganisms and/or their metabolites. The most successful advancement of mineral biotechnology so far is on copper, uranium, nickel-cobalt and gold bearing ores. Treatment of mineral industry effluents by microorganisms, with incidental recovery of some Metal values constitutes an equally important area of biomineral processing. The most common method followed for leaching or Extraction of Metal values is through shake flask (a lab scale method) followed by bioreactors or percolation columns (a bench scale method) and finally to heap leaching (a pilot scale method). Bio-leaching of mono- and multiple-sulphides is now coming to be known as an established commercial process. The present review discusses the microorganisms involved in biomineral processing, mechanism of Metal Extraction, molecular methodologies adopted for microbial identification with our experience on application of microorganism.