Results 181 to 190 of about 8,700 (211)

Arsenopyrite enrichment by column flotation

Minerals Engineering, 1993
Abstract Arsenic-rich, gold-bearing pyrite concentrates may be further enriched in arsenic to assist subsequent Au beneficiation. Among several amines tested in refloating a local Chalkidiki pyrite concentrate, 2-coco 2-methyl ammonium chloride proved successful by raising the grade from 9% to 22%, although total solids recovery was low. The use of a
P. Mavros, K.A. Kydros, K.A. Matis
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Electrolytic oxidation of arsenopyrite slurries

Minerals Engineering, 1993
Abstract Arsenopyritic (FeAsS) gold ore is usually refractory because cyanide solution cannot react with the gold, which is locked within the sulphide lattice. Destruction of the arsenopyrite lattice by electrolytic oxidation is a possible low temperature pretreatment option for refractory arsenopyritic gold ore.
H.G. Linge, W.G. Jones
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Electrochemical study of arsenopyrite weathering

Physical Chemistry Chemical Physics, 2002
Cyclic voltammograms and capacitance measurements are presented to characterize the mineral response at relatively moderate environmental conditions, pH 4.5 and T = 25 °C. The experiments involve examining the rates of oxidation and the surface morphology of arsenopyrite, which is oxidized abiotically.
Almeida, CMVB, Giannetti, B. F.
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Mechano-chemical oxidation of arsenopyrite

Minerals Engineering, 2019
Abstract This paper presents the results from the investigation of arsenopyrite oxidation via mechano-chemical activation, using a stirred mill. Water and hydrogen peroxide were chosen as the lixiviant and oxidant, respectively, and maintained at a relatively low temperature (50 °C).
Larissa Koroznikova, Stafford McKnight, Jean-Pierre Veder, Jason Giri, Samayamutthirian Palaniandy, Gordon Williams   +5 more
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Arsenopyrite: a spectroscopic investigation of altered surfaces

Mineralogical Magazine, 1989
AbstractSurfaces of a natural sample of arsenopyrite (FeAsS) were oxidized by a range of inorganic oxidants, and the resultant surface alteration products studied using various spectroscopic techniques. The oxidants used were air during heating to relatively low temperatures (150°C), steam, ammonium hydroxide, hydrogen peroxide, and sulphuric acid ...
Richardson, S., Vaughan, D. J.
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The ferric leaching kinetics of arsenopyrite

Hydrometallurgy, 1999
In this investigation batch, ferric leaching experiments were carried out in a 100 ml jacketed vessel maintained at 25°C. The parameters varied during the course of the experimental program included the initial redox potential, the total iron concentration, the solids concentration and the pH of the leaching solution.
R. Ruitenberg, G.S. Hansford, M.A. Reuter, A.W. Breed   +3 more
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Arsenopyrite dissolution rates in O2-bearing solutions

Chemical Geology, 2010
Abstract Arsenopyrite dissolution was studied by means of long-term, stirred and non-stirred flow-through experiments in the pH range of 1 to 9 at 25, 50 and 70 °C and at different input dissolved-O2 concentrations (from 0.2 to 8.7 mg L− 1). At pH lower than 4, aqueous iron, which is mainly in the ferrous form, and arsenic are stoichiometrically ...
Asta MP, Cama J, Ayora C, Acero P, DE GIUDICI, GIOVANNI BATTISTA   +4 more
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Thermal decomposition of mechanically activated arsenopyrite

Journal of Thermal Analysis, 1994
The changes in specific surface area and structure disorder of mechanically activated arsenopyrite were investigated. The rate of nonoxidative decomposition of mechanically activated arsenopyrite was increased almost 10-times when compared with nonoxidative decomposition of a non-activated sample.
P. Baláz, M. Balassaová
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Thioarsenate formation upon dissolution of orpiment and arsenopyrite

Chemosphere, 2012
Thioarsenates were previously determined as dominant species in geothermal and mineral waters with excess sulfide. Here, we used batch leaching experiments to determine their formation upon weathering or industrial leaching of the arsenic-sulfide minerals orpiment (As(2)S(3)) and arsenopyrite (FeAsS) under different pH and oxygen conditions.
Elke, Suess, Britta, Planer-Friedrich
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New Semiconducting Arsenopyrite-type Compounds

Nature, 1964
IN a recent paper1 we reported on semiconductivity in CoSb2-type compounds. The ternary analogues of these polycompounds are formed by the arsenopyrite group. The monoclinic minerals arsenopyrite, FeAsS, and gud-mundite, FeSbS, closely correspond to the mineral safflorite, CoAs2.
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