The Bacterial Oxidation of Gold-bearing Pyrite/arsenopyrite Concentrates PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download The Bacterial Oxidation of Gold-bearing Pyrite/arsenopyrite Concentrates PDF full book. Access full book title The Bacterial Oxidation of Gold-bearing Pyrite/arsenopyrite Concentrates by Katherine Malatt. Download full books in PDF and EPUB format.
Author: Katherine Malatt
Publisher:
ISBN:
Category :
Languages : en
Pages : 528
Get Book Here
Book Description
This study sought to determine the rates of ferric sulflate oxidation and bacterial oxidation of arsenopyrite. Ferric oxidation of arsenopyrite revealed unusual temperature related behaviour with the fastest leaching rate observed at 50οC above this the mineral surface became covered by a jarosite phase which hindered the reaction. Use of a flat disk of arsenopyrite allowed surface area based rates to be determined. These were similar to those for sized slurries under similar conditions. The rates of bacterial and ferric oxidation of arsenopyrite were also found to be comparable. This is further evidence for the "indirect" mechanism of bacterial leaching.
Author: Katherine Malatt
Publisher:
ISBN:
Category :
Languages : en
Pages : 528
Get Book Here
Book Description
This study sought to determine the rates of ferric sulflate oxidation and bacterial oxidation of arsenopyrite. Ferric oxidation of arsenopyrite revealed unusual temperature related behaviour with the fastest leaching rate observed at 50οC above this the mineral surface became covered by a jarosite phase which hindered the reaction. Use of a flat disk of arsenopyrite allowed surface area based rates to be determined. These were similar to those for sized slurries under similar conditions. The rates of bacterial and ferric oxidation of arsenopyrite were also found to be comparable. This is further evidence for the "indirect" mechanism of bacterial leaching.
Author: Soumitro Nagpal
Publisher:
ISBN:
Category : Bacterial leaching
Languages : en
Pages : 264
Get Book Here
Book Description
Author: D. M. Miller
Publisher:
ISBN:
Category : Gold
Languages : en
Pages : 254
Get Book Here
Book Description
Author: Douglas E. Rawlings
Publisher: Springer Science & Business Media
ISBN: 3662061112
Category : Science
Languages : en
Pages : 302
Get Book Here
Book Description
Biomining is the use of microorganisms in the recovery of metals from ores. During bioleaching, metals such as copper, nickel or zinc are oxidized through microbial action from the water-insoluble sulfide to the soluble sulfate forms. Although gold is inert to microbial action, microbes can also be used in gold recovery from certain types of ores because as they oxidize the ore, they open up its structure, thereby allowing a gold-solubilizing agent such as cyanide to penetrate the ore. The book describes several industrial bioleaching and biooxidation processes as well as the underlying theory and biology of the microbes involved.
Author: P. Bhakta
Publisher:
ISBN:
Category : Gold
Languages : en
Pages : 20
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
The liberation of refractory gold from sulphides during bacterial oxidation was investigated using arsenopyrite and pyrite crystals isolated from a refractory Barberton gold ore. Polished sections of the crystals were prepared and the mode of occurrence of gold within these sulphides was determined, using a scanning electron microscope (SEM) and an electron microprobe. It was found that the arsenopyrites and pyrites are chemically zoned, due to alternating enrichment and depletion in the As-content. The submicroscopic gold is heterogeneously distributed in the arsenopyrite and is specifically enriched in zones with a relatively moderate Fe-content, a high As-content and a low S-content. The As-rich zones in the pyrite are also enriched in submicroscopic gold. Particulate gold occurs as inclusions within arsenopyrite and pyrite mainly at the contacts between different zones. Polished sections were suspended in the bacterial leach pulp in an air-stirred vessel for various periods of time. The effects of the sulphide oxidation were monitored by observations of the leached sections under both an optical microscope and a SEM. The As-rich zones in both arsenopyrite and pyrite crystals were preferentially and rapidly oxidized. Structural deviations in the sulphide lattices, such as zone contact, cracks, dislocation and contacts between different sulphide generations, were also sites of initial bacterial attack. These results show that the composition of the sulphides plays a fundamental role in determining the sites and rates of bacterial oxidation. Due to this preferential oxidation of high gold-bearing areas in the sulphides, large amounts of particulate and submicroscopic gold will be liberated during the very early stages of sulphide oxidation. The As-poor zones in both the arsenopyrite and pyrite crystals were oxidized during the later stages of bacterial oxidation, which will result in the slower liberation of the remaining gold.
Author: Mike D. Adams
Publisher: Elsevier
ISBN: 0444636706
Category : Science
Languages : en
Pages : 1050
Get Book Here
Book Description
Gold Ore Processing: Project Development and Operations, Second Edition, brings together all the technical aspects relevant to modern gold ore processing, offering a practical perspective that is vital to the successful and responsible development, operation, and closure of any gold ore processing operation. This completely updated edition features coverage of established, newly implemented, and emerging technologies; updated case studies; and additional topics, including automated mineralogy and geometallurgy, cyanide code compliance, recovery of gold from e-waste, handling of gaseous emissions, mercury and arsenic, emerging non-cyanide leaching systems, hydro re-mining, water management, solid–liquid separation, and treatment of challenging ores such as double refractory carbonaceous sulfides. Outlining best practices in gold processing from a variety of perspectives, Gold Ore Processing: Project Development and Operations is a must-have reference for anyone working in the gold industry, including metallurgists, geologists, chemists, mining engineers, and many others. - Includes several new chapters presenting established, newly implemented, and emerging technologies in gold ore processing - Covers all aspects of gold ore processing, from feasibility and development stages through environmentally responsible operations, to the rehabilitation stage - Offers a mineralogy-based approach to gold ore process flowsheet development that has application to multiple ore types
Author: Christine C. Gaylarde
Publisher: Cambridge University Press
ISBN: 9780521417570
Category : Medical
Languages : en
Pages : 392
Get Book Here
Book Description
The research in metal-microbe interactions is reviewed, for researchers and engineers.
Author: John Marsden
Publisher: SME
ISBN: 9780873352406
Category : Science
Languages : en
Pages : 688
Get Book Here
Book Description
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.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
A mechanistic model is derived for the non-linear relationship between the release of gold and the percentage of sulphide oxidized during the bacterial leaching of mixed pyrite and arsenopyrite concentrates. The original ratio of pyrite to arsenopyrite, the ratio of the rate constants for their breakdown, and the distribution of gold between these two minerals are the parameters used for the fitting of curves to the experimental data. During bacterial leaching, cylindrical pores develop along weaknesses in the sulphide lattice, which are therefore preferred sites of bacterial corrosion. If the gold is in a particulate form and preferentially associated with such structural weaknesses, the release of gold occurs at an accelerated rate that does not conform to the numerical model.
