Download or read book Evaluation of Electrochemical Mechanisms for the Adsorption of Gold Cyanide on Activated Carbon written by Warren Glen Jones and published by . This book was released on 1993 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Mechanism of the Adsorption of Gold Cyanide on Activated Carbon written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray photoelectron spectroscopy showed that the adsorption of gold cyanide on carbon in the presence or absence of electrolytes and acids proceeds by the same mechanism. Although the identity of the gold cyanide adsorbate is not known, the mechanism appears to have an initial adsorption stage that involves the adsorption of an ion pair: M(n+)[Au(CN)2(-)]n, where M(n+) is a metal ion (for example Na+, K+ and Ca(2+) that has a lower solubility than the Au(CN)2(-) anion in the adsorption medium, followed by a reduction step in which either a sub-stoichiometric Au(CN)x surface species or a cluster-type compound of gold is formed.
Download or read book Hydrometallurgy 2008 written by and published by SME. This book was released on 2008 with total page 1201 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Investigation of Techniques for Removal of Cyanide from Electroplating Wastes written by A. K. Reed and published by . This book was released on 1972 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasingly stringent stream discharge regulations have prompted an assessment of the current technology available for application to the metal finishing waste treatment problem, specifically in regard to smaller operations. Experimental laboratory and bench scale studies were then conducted on several unconventional wastewater treatment methods, including ion flotation, activated carbon adsorption, acidification volatilization, and solvent extraction. A demonstration pilot plant study was also conducted on the activated carbon process employing actual rinse waters from a zinc cyanide plating operation. The pilot scale activated carbon system was operated at 99% efficiency of cyanide removal, while providing for the complete recovery and regeneration of copper. Cost estimates for carbon sorption process are given.
Download or read book Effect of Metal Impurities on the Adsorption of Gold by Activated Carbon in Cyanide Solutions written by S. A. N. Sheya and published by . This book was released on 1989 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gold Metallurgy and the Environment written by Sadia Ilyas and published by CRC Press. This book was released on 2018-02-19 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives an overview of all the gold extraction processes along with their mechanistic study and environmental impact. Reviews extraction techniques previously employed as well as recently evolved technology for gold leaching, provides technical flow sheets for processing of ores with a diversity of lixiviants and offers a compulsory overview of every gold processing technique It also discusses recent integrated techniques including hydro- and bio-metallurgical techniques with examples
Download or read book The Mechanism of Adsorption of Dicyanoaurate on Activated Carbon written by Arturo Sabio Ibrado and published by . This book was released on 1992 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Chemical Behaviour of Cyanide in the Extraction of Gold Part 2 Mechanisms of Cyanide Loss in the Carbon in pulp Process written by and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The major cause of cyanide loss in carbon-in-pulp (CIP) plants is identified as being due to the reaction of cyanide with base metals and sulphides during leaching. Some cyanide is also lost in the adsorption tanks as a result of oxidative and adsorption reactions with the activated carbon. The high rates of cyanide loss in the elution and electrowinning stages are attributable to hydrolytic decomposition and anodic oxidation, respectively. However, the relative amount of cyanide lost during these two stages is small for a given amount of ore treated.
Download or read book The Adsorption of Gold Cyanide on Activated Charcoal written by Steven Nels Dixon and published by . This book was released on 1977 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Mechanism of Adsorption of Aurocyanide Onto Activated Carbon written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanism of adsorption of aurocyanide onto activated carbon and its subsequent elution are examined in this study, with special reference to the effects of acid and alkali treatment on the system. The results, including a careful analysis of the distribution of all ions in the adsorption and elution processes, are discussed, and evidence for the adsorption and elution mechanisms involved is presented. It is proposed that, under normal plant conditions, aurocyanide is extracted onto activated carbon in the form of an ion pair, M(n+)[Au(CN)2(-)]n, and eluted by hydroxide or cyanide. The hydroxide or cyanide ions react with the carbon surface, rendering it relatively hydrophilic with a decreased affinity for neutral species. Additional adsorption mechanisms are shown to operate under other conditions of ionic strength, pH, and temperature, and it is suggested that this may account in part for the lack of agreement among workers.
Download or read book Metals Abstracts written by and published by . This book was released on 1998 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of the South African Institute of Mining and Metallurgy written by South African Institute of Mining and Metallurgy and published by . This book was released on 1987 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adsorption Characteristics of Activated Carbon written by P. M. Afenya and published by . This book was released on 1993 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Activated carbon has been used in a variety of ways for many years. Some of the early applications are in the removal of color, odor taste and objectionable impurities from solutions. In recent years activated carbon has attained new prominence as a material for adsorption of gold and silver cyanides from cyanide-leach gold ores. This new use has a attracted many researchers to investigate the mechanism of aurocyanide adsorption on activated carbon. This paper reviews the chemical and structural characteristics of activated carbon and its mode of adsorption of organic and inorganic species from solutions. Emphasis is given to the study of the mechanism of aurocyanide adsorption. Recent use of X-ray photoelectron spectroscopy for investigating the nature of the adsorbed aurocyanide species will be discussed. [Author's abstract].
Download or read book The Chemical Behaviour of Cyanide in the Extraction of Gold 1 Kinetics of Cyanide Loss in the Presence and Absence of Activated Carbon written by and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The kinetics of cyanide loss were found to be first order under any given set of conditions, allowing rate constants to be easily determined. At room temperature and in the absence of activated carbon, some cyanide is lost by hydrolysis to hydrogen cyanide, but this does not occur to any significant extent at pH values higher than about 10. A higher rate of hydrolysis occurs when air-agitation is used. When activated carbon is present, an additional carbon-catalysed oxidation reaction is responsible for a fairly high loss of cyanide. The evidence indicates a reaction mechanism that consumes oxygen and produces cyanate ion. Some of the cyanate thus produced decomposes to form a mixture of ammonia, carbonate, and urea, depending on the solution conditions. Additional cyanide is lost as a result of the adsorption of sodium cyanide by the activated carbon. At high temperatures, an additional hydrolysis reaction, which involves the formation of ammonium formate as an intermediate, occurs and is responsible for a high loss of cyanide, leading ultimately to the formation of ammonia, hydrogen, and carbon dioxide. The presence of activated carbon has no effect on the rate of this reaction.
Download or read book The Mechanism of Gold Adsorption on Carbon from Cyanide Solution written by Thompson Njambe Mambe and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Clean Coal Technologies written by Rajesh Kumar Jyothi and published by Springer Nature. This book was released on 2021-05-10 with total page 665 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the state of art of the several advanced approaches to beneficiation of coal. The influence of recent technology attains the advantages of processing coal, purification studies, rheological behavior, and the mineral beneficiation. The experts collected in this volume have contributed significantly to the enrichment in the in depth knowledge not only in context of working knowledge, but also future prospects of clean coal technology.
Download or read book Fundamentals of the Elution of Gold Cyanide from Activated Carbon written by Pieter Francois Van der Merwe and published by . This book was released on 1991 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt:
