Author
R. Y. Wan
Bio: R. Y. Wan is an academic researcher. The author has an hindex of 1, co-authored 1 publications receiving 26 citations.
Papers
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01 Dec 1991-Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science
TL;DR: In this paper, the electrochemical oxidation of a natural pyrite electrode in sterile and inoculated sulfuric acid solutions has been studied using both linear-scan voltammetric and chronoamperometric techniques.
Abstract: The electrochemical oxidation of a natural pyrite electrode in sterile and inoculated sulfuric acid solutions has been studied using both linear-scan voltammetric and chronoamperometric techniques. The bacteria used consist of a pyrite-adapted mixed culture ofThiobacillus ferrooxidans. The influence of the iron concentration and the presence of bacteria have been studied at different pH values. The results from these electrochemical measurements are discussed in conjunction with surface characterization.
27 citations
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TL;DR: In this article, a review deals with abiotic/biotic modes of pyrite oxidation and the mechanistic involvement of OH, O2, and Fe3+ in the process in low/high pH environments.
Abstract: Sulfide oxidation, part of sulfur's biotic/abiotic cycle, is an important natural phenomenon. However, because of the sulfide's association with metallic ores and fossil fuels in the form of pyrite (FeS2) and the world's increasing demand for metals and fossil fuels, sulfide oxidation in nature is in some state of perturbation. This perturbation, which results from land disturbances (e.g., mining, and/or ore processing), produces acid drainage often enriched with heavy metals. This acid drainage, commonly referred to as acid mine drainage (AMD), has become an economic and environmental burden. This review deals with abiotic/biotic modes of pyrite oxidation and the mechanistic involvement of OH‐, O2, and Fe3+ in the pyrite oxidation process in low/high pH environments. Also included is recent evidence on the potential involvement of CO2 in catalyzing pyrite oxidation in near‐neutral and alkaline environments. Finally, the review deals with various pyrite‐oxidation control approaches, the merits of...
559 citations
Book•
12 Oct 1998
TL;DR: In this article, the chemistry and management of salt-affected Soils and Brackish Waters are discussed, and a number of technologies are described. But none of them are suitable for use in the field of water treatment.
Abstract: WATER CHEMISTRY AND MINERAL SOLUBILITY. Physical Chemistry of Water and Some of Its Constituents. Solution/Mineral-Salt Chemistry. SOIL MINERALS AND SURFACE CHEMICAL PROPERTIES. Soil Minerals and Their Surface Properties. Sorption and Exchange Reactions. ELECTROCHEMISTRY AND KINETICS. Redox Chemistry. Pyrite Oxidation Chemistry. Reaction Kinetics in Soil-Water Systems. SOIL DYNAMICS AND AGRICULTURAL-ORGANIC CHEMICALS. Organic Matter, Nitrogen, Phosphorus and Synthetic Organics. COLLOIDS AND TRANSPORT PROCESSES IN SOILS. Soil Colloids and Water-Suspended Solids. Water and Solute Transport Processes. The Chemistry and Management of Salt-Affected Soils and Brackish Waters. LAND-DISTURBANCE POLLUTION AND ITS CONTROL. Acid Drainage Prevention and Heavy Metal Removal Technologies. SOIL AND WATER: QUALITY AND TREATMENT TECHNOLOGIES. Water Quality. Soil and Water Decontamination Technologies. Appendix. Suggested and Cited References. Index.
304 citations
01 Jan 2007
TL;DR: The present work focuses on the application of bioinformatics and genome biology to advance the understanding of bioleaching microorganisms, as well as other applications, including bioflotation and bioflocculation of relevance to minerals.
Abstract: Preface Section I - Fundamentals, microorganisms and mechanisms Microorganisms involved in bioleaching and nucleic acid-based molecular methods for their identification and quantification Axel Schippers Mechanisms and biochemical fundamentals of bacterial metal sulfide oxidation Thore Rodwerder and Wolfgang Sand Electrochemical techniques used to study bacterial-metal sulfides interactions Denise Bevilaqua, Heloisa A. Acciari, Assis V. Benedetti and Oswaldo Garcia Jr Electrochemical mechanism of leaching. Influence of the presence of catalytic ions and bacteria Antonio Ballester, Maria Luisa Blazquez, Felisa Gonzalez and Jesus A. Munoz Recovery of zinc, nickel, cobalt and other metals by bioleaching Marisa R. Viera, Cristina M. Pogliani and Edgardo R. Donati Bioleaching of metals in neutral and slightly alkaline environment Aleksandra Sklodowska and Renata Matlakowska Section II - Bioreactors and Bioheaps Bioleaching of sulfide minerals in continuous stirred tanks Dominique Henri Roger Morin Bioreactor design fundamentals and their application to gold mining Fernando Acevedo and Juan Carlos Gentina Air-lift reactors: characterization and applications in biohydrometallurgy Alejandra Giaveno, Laura Lavalle, Patricia Chiacchiarini and Edgardo R. Donati Principles, mechanisms and dynamics of chalcocite heap bioleaching Jochen Petersen and David G. Dixon Section III - Genetics and Molecular Biology The use of bioinformatics and genome biology to advance our understanding of bioleaching microorganisms Raquel Quatrini, Jorge Valdes, Eugenia Jedlicki and David S. Holmes Proteomics and metaproteomics applied to biomining microorganisms Carlos A. Jerez Cell-cell communication in bacteria: A promising new approach to improve bioleaching efficiency? Susana Valenzuela,Alvaro Banderas, Carlos A. Jerez and Nicolas Guiliani Section IV - Other Applications Bioflotation and bioflocculation of relevance to minerals Bioprocessing K. Hanumantha Rao and S. Subramanian Desulphurization of gaseous emissions containing hydrogen sulfide Jose Manuel Gomez and Domingo Cantero Index
149 citations
TL;DR: In this paper, the authors provide a fundamental understanding of the various mechanisms involved in microbial leaching of sulfide minerals and provide a brief look at the various factors affecting this process.
135 citations
TL;DR: A detailed review of the current state of scientific knowledge with regard to the magnitude of the problem, the chemistry and mechanism of sulfide mineral oxidation and acid mine drainage formation, the role of microorganisms in ARD formation process, and the proposed approaches for the treatment, control, and prevention of acid rock drainage (ARD) formation is presented in this article.
Abstract: The exploitation of coal and metallic mineral resources worldwide invariably results in the production of large quantities of overburden, gangue, and tailings materials containing significant amounts of sulfide minerals. These sulfide minerals, which include sphalerite, chalcopyrite, galena, and other complex sulfides, are often disseminated in pyrite, which is the most abundant sulfide mineral in the earth's crust. Once exposed to water and oxygen through mining and mineral processing operations, these sulfides become immediately susceptible to chemical and biochemical oxidation with the consequent production of highly acidic, metal-laden leachates, which are generally referred to as acid rock drainage (ARD) or acid mine drainage (AMD). This ARD production, which can be sustained for hundreds of years, has become the single biggest environmental problem facing the mining and mineral industry. Untreated acid rock drainage leads to serious contamination of large areas of land, as well as surface and ground water resources. The seriousness of the problem has led to major research efforts to find solutions. However, effective ARD treatment and prevention solutions have eluded the scientific community over the past decades. This paper presents a detailed review of the current state of scientific knowledge with regard to the magnitude of the problem, the chemistry and mechanism of sulfide mineral oxidation and ARD formation, the role of microorganisms in ARD formation process, and the proposed approaches for the treatment, control, and prevention of ARD formation. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
117 citations