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Showing 1 to 20 of 789 for “"leaching"”.
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Investigation of Chalcopyrite Leaching Kinetics by Alternative Leaching Chemicals
… sulfide mineral due to passivation during leaching process in a conventional leaching system. In this study, alternative lixiviants, MSA (methanesulfonic acid, CH4SO3) and sulfurous acid (H2SO3) were investigated to enhance leaching kinetic. In addition, alternative oxidants, hydrogen …
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Modeling chalcopyrite leaching kinetics
… sulfides and also one of the most refractory for leaching. Several processing routes have been proposed to overcome drawbacks associated with environmental problems related to copper extraction from this mineral. Atmospheric leaching in acidic ferric sulfate is regarded as being particularly …
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The ferric leaching of pyrite
The bioleaching of pyrite has been found to occur via an indirect mechanism. Ferric iron leaches the pyrite, and is reduced to ferrous iron. Bacteria such as Thiobacillus ferrooxidans oxidise the ferrous iron to ferric iron, thus maintaining a high redox potential. In this thesis, the effect of the …
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Risk assessment formulation for nitrate leaching
… (Ver 2.1) model was used to simulate NO₃-N leaching below the root zone for different land application rates of liquid dairy waste for fields in Georgia and Texas. Probability distributions of yearly-maximum nitrate concentrations were developed for each application rate at each site using …
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Acid Leaching of SHS Produced MgO/TiB2
… (TiB₂) and MgO as final products. Selective acid leaching is used to remove the MgO leaving high purity TiB₂ powder. The SHS method to produce TiB₂ is attractive because of the relatively low temperature required to initiate the reaction, fast reaction time, and product purity. This study …
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Effect of Various Saturation Levels, Leaching Solution pH, and Leaching Cycle on Electrical Conductivity from Coal Mine Spoil Leachate
… column studies utilized an unsaturated bi-weekly leaching design to evaluate the behavior of overburden with respect to TDS, pH, and trace metals. The objective of this study was to determine the effects of column saturation, leaching solution chemistry, and leaching cycle on the release of TDS …
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Kinetics of the ferric sulphate leaching of sphalerite and sphalerite/pyrite mixtures : a study of the chemical leaching of base metal minerals under conditions similar to that of bio-leaching by thiobacilli
… dissertation is an investigation of-the ferric leaching of zinc from sphalerite. A further aspect of this study was an investigation of the influence of pyrite on the dissolution rate of sphalerite due to possible galvanic interactions. This study is one component of a larger study of the …
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Leaching of amylose from wheat and corn starch
Call number: LD2668 .T4 GRSC 1989 S55
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Leaching of amylose from wheat and corn starch
Call number: LD2668 .T4 GRSC 1989 S55
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Predictive Modeling of Nuclear Waste from Leaching Behavior
Made available in DSpace on 2017-07-06T18:56:23Z (GMT). No. of bitstreams: 3 Simonson_Scott_A_MS.pdf: 18773490 bytes, checksum: 4ed0b8b37642d609a0f50a1749cec89e (MD5) Simonson_Scott_A_MS_ABS.pdf: 472178 bytes, checksum: aa3ad13ccb9a02b02c0ae1ef9cd01db7 (MD5) license.txt: 4813 bytes, checksum: …
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A study of leaching tests for cement stabilised waste
… was subjected to batch, column, and dynamic leaching tests, and the leaching behaviour of arsenic, copper, lead, selenium, and zinc was investigated. Batch tests included the Australian Bottle Leaching Procedure (ABLP, AS 4493.3-1997), Toxicity Characteristic Leaching Procedure (TCLP, USEPA …
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Effects of adding acid plant sulfur on heap leaching
… ore deposits are found across the world and heap leaching of copper has been implemented effectively for years. The ore is broken down to copper ions and elemental sulfur in the heap. Acid plants are used in mines to replenish the raffinate leaching the heaps which consists of sulfuric acid. …
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Effect of scale of operation on heap leaching performance
… contribute towards the differences observed in leaching performance between laboratory-scale columns versus commercial-scale heaps was investigated. Furthermore, the contributions of segregation and stratification, which are absent from columns but unavoidable in heaps, were also investigated. …
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Toxicity characteristic leaching procedure analysis of dye containing sludges
… sludge using the Toxicity Characteristic Leaching Procedure (TCLP) was investigated. In addition to the dyestuffs, metals and other organic compounds which also leached were identified. Only small amounts of color were detected in the TCLP extracts; the mean ADMI color values for …
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Sorption and leaching of glyphosate on partly sealed urban areas
Anlass für die Untersuchungen war der Einsatz des Herbizids Glyphosat zur Unkrautbekämpfung auf Gehwegen. Da das für den Gehwegbau eingesetzte Material, geringere Sorptionskapazitäten für Glyphosat als landwirtschaftliche Böden aufweist, war das Ziel dieser Arbeit abzuschätzen, ob nach Applikation …
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Analysis of Kyrock for Leaching of Impurities in Synthetic Rainwater
… Synthetic rainwater was prepared to examine the leaching of compounds and the leachate was analyzed using liquid chromatography mass spectroscopy and gas chromatography mass spectroscopy.</p>
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Characterization of Trace Metal Leaching from Maryland Coal Fly Ashes
… were analyzed for arsenic, copper, and chromium leaching as function of pH using batch-type water leach tests (pH 4-10). Leach tests results showed that significant Cu release occurred only at pH ~4.3 and dissolved Cr concentrations typically increased with increasing pH. Cr(VI) was determined as …
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On the progression of leaching from large particles in heaps
Although heap leaching is by now a well-established technology choice in the mining industry, the process remains limited by low recoveries and long extraction times. It is becoming increasingly clear that the successful application of heap leaching technology will ultimately depend on having a …
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Fundamental studies of heap leaching hydrology using magnetic resonance imaging
The recovery of mineral from ore in the heap leaching process requires the mineral to come into contact with the leaching solution. However, heap hydrology is prone to non-uniform behaviour due to the inhomogeneity of the ore particles and the heap structure. The primary aim of this thesis was …
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Mechanistic Modeling of Nuclear Waste Form Leaching by Aqueous Solutions
Predictive modeling of nuclear waste form leaching requires a mechanistic representation of the processes and factors controlling the rates at which species are released from the solid waste form into the contacting aqueous solution. A basic distinction is made among bulk, surface, and leachant …
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