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 Chemistry of Gold Extraction written by John Marsden and published by SME. This book was released on 2006 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extensively revised and updated, this edition provides the broad base of knowledge required by all working in the gold extraction and gold processing industries. It bridges the gap between research and industry by emphasizing practical applications of chemical principles and techniques.
Download or read book Precision Process Technology written by M.P.C. Weijnen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt: New process technology strategies are required to cope with the future. Fossil feedstocks are losing ground in favour of renewable feedstocks and secondary resources. Conventional processing routes using thermal `sledgehammer' techniques are replaced by highly selective (bio)catalytic conversions. The future process engineer is neither allowed to think in terms of unit operations, nor to take for granted the conventional practice of continuous steady state processing. Hybrid systems and transient operations are more and more frequently encountered. The continuing impressive progress being made in process modelling and control will revolutionize the process industries. In the new generation of chemical production processes the keyword is precision. Precision in terms of selectivity and of efficiency, is required to maximize the utilisation of materials and energy. Moreover, enhanced precision is needed to exploit the quality of materials and energy to the full extent. Only by reducing the squandering of materials, energy and quality will a harmonious relationship be established between the process industries, the economy, and the environment. Process integration, as well as an integrated effort by the disciplines involved in process technology, will be of crucial importance in attaining the goals of precision process technology. These emerging strategies involve an active exchange of tools and ideas between a variety of disciplines, not only in plant design and operation, but even more in the early stages of process development and design. By looking from various angles at what the future has in store for the process industries, this volume systematically lifts the corners of the veil and may inspire to establish a new tradition of precision in process technology.
Download or read book AusIMM written by Australasian Institute of Mining and Metallurgy. Conference and published by . This book was released on 1998 with total page 530 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 1990 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unrestricted Mintek Publications written by and published by . This book was released on 1987 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AusIMM 98 the Mining Cycle written by Australasian Institute of Mining and Metallurgy. Conference and published by . This book was released on 1998 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oxidation of Iron Complexed Cyanide Compounds in Manufactured Gas Plant Groundwater written by Art J. Griffith and published by . This book was released on 1992 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impurity Control and Disposal in Hydrometallurgical Processes written by Metallurgical Society of CIM and published by Metallurgical Society of the Canadian Institute of Mining, Metallurgy and Petroleum = La Société de la métallurgie de l'institut canadien des mines, de la métallurgie et du pétrole. This book was released on 1994 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Precious Metals Bulletin written by and published by . This book was released on 1990 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Engineering Abstracts written by and published by . This book was released on 1990 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Gold Ore Processing written by Mike D. Adams and published by Elsevier. This book was released on 2005-12-02 with total page 1077 pages. Available in PDF, EPUB and Kindle. Book excerpt: The gold processing industry is experiencing change. As free-milling and oxide ores become depleted, more complex polymetallic and refractory ores are being processed, coupled with increasing pressure for stricter environmental compliance. Recent years have also seen a steady reduction in mineral processing and metallurgy graduates and a gradual loss of older operating experience. A contribution to documenting current and future best practice in gold ore processing seems timely.The focus of this volume is on advances in current gold plant operation, from conception to closure; chapters also cover innovations at the bench and pilot-scale level that would be expected to find commercial application at some stage. Sufficient coverage is also given to the chemistry and engineering aspects. The general principle behind the structure of the volume is that of flowsheeting based on unit operations and applied to a mineralogical classification of gold ore types. From concept to closure, this book covers all unit operations, mineralogies and processes that are relevant to dealing with today's complex orebodies.Practical experience is vital to the successful development, operation and closure of any operation. The 42 chapters have been contributed by a total of 66 authors and co-authors who are experts from countries spanning the globe, and representing exhaustive practical knowledge covering many disciplines relevant to gold processing.* Current best practice as elucidated by a select panel of experts in the field* Innovations at the bench and pilot-scale level that would be expected to find commercial application at some stage* Mineralogical-based approach to flowsheeting
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 Chemical Abstracts written by and published by . This book was released on 1990 with total page 2210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EPD Congress 1992 written by Minerals, Metals and Materials Society. Extraction and Processing Division and published by Minerals, Metals, & Materials Society. This book was released on 1992 with total page 1406 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the third in a series of proceedings documenting the EPD Congress, held yearly at the TMS Annual Meeting. State-of-the-art information on the extraction and processing of a wide range of materials is contained in the volume.
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 The Absorption of Gold Cyanide Onto Activated Carbon 1 The Kinetics of Absorption from Pulps written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An account is given of the development of a relatively simple model that describes the kinetics of the absorption of gold cyanide on activated carbon. The model is based on the treatment of the carbon-solution interface as a homogeneous boundary across which gold is transported at a rate determined by the rate of mass transport to and from the interface. Rate equations derived from this model describe the results of various kinetic experiments under continuous or batch conditions in the laboratory and on operating pilot and full-scale plants.
