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Showing 1 to 20 of 65 for “"Xanthate"”.
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Investigation of cellulose xanthate
I have attempted to synthesize cellulose xanthate in anhydrous liquid ammonia, and to analyze the product for combined sodium and sulphur, with the hope of determining the exact chemical composition of each C₆ unit of cellulose xanthate. It is the purpose of this work to study the xanthation of …
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The flotation of pyrite using xanthate collecters
… hydrophilic ferric hydroxide. The addition of a xanthate collector improved the flotation properties of pyrite at all pHs. In acidic solutions the main effect observed was on the rate of pyrite recovery and on the grade of the concentrates. In alkaline solutions the addition of a xanthate …
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Thermodynamic studies of xanthate adsorption on pyrite
… enthalpy (ΔH°) changes, for the adsorption of xanthates on pyrite. The electrochemical technique is based on the measurement of the open-circuit potentials of a pyrite electrode immersed in xanthate solutions at various temperatures. The thermochemical technique involves the determination of …
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Nonstoichiometry of chalcocite in water-xanthate systems
… copper sulfides, both with and without xanthate. Stability regions for copper xanthates were also shown to be dependent on the sulfur oxidation state. As oxidation proceeded from elemental sulfur to sulfate, the copper xanthate stability region extended to lower potentials, directly …
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The attempted plasticization of cellulose from cellulose xanthate
… suggested that a film prepared from a cellulose xanthate, in which the fiber form had been destroyed by some action other than by dilute alkali, should have interesting properties. The possibilities of such a material might be much greater if the destruction of the fiber form were brought about …
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Kinetic Studies of Sulfide Mineral Oxidation and Xanthate Adsorption
… to float and depress different sulfide minerals. Xanthate, a thiol collector, has gained immense usage in sulfide minerals flotation. However, some sulfides are naturally hydrophobic and may float without a collector. Iron sulfides, such as pyrite and pyrrhotite, are few of the most abundant …
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Thermodynamics and electrochemistry of the chalcocite-potassium ethyl xanthate system
… formation of selected species, and iv) minimum xanthate additions required to form CuX and CuX₂. These information can be used as a guide in predicting the optimum conditions for flotation and leaching of chalcocite. The upper limiting potentials predicted from the thermodynamic calculations are …
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The fractionation of cellulose xanthate by means of its derivatives
… obtained from the fractionation of cellulose xanthate diethylacetamide by Fink, Stahn, and Matthes; the results obtained here indicate that there is a definite variation of the degree of substitution from fraction to fraction. And that therefore cellulose xanthate as commercially prepared is …
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Separation of cobalt and copper from nickel by means of potassium xanthate
Made available in DSpace on 2016-11-09T23:48:03Z (GMT). No. of bitstreams: 2 5956999_opt.pdf: 2975908 bytes, checksum: c5e4d03ecfd9cd9d14e2a55ef6226af6 (MD5) license.txt: 4183 bytes, checksum: 1dcc2037833d76bede73d5717587543b (MD5) Previous issue date: 1894
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Investigation of pyrite and sphalerite flotattion with potassium amyl and ethyl xanthate, An
Includes bibliographical references (pages 78-80).
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Studies on the reactivity of thiophosphate/thiophosphinate and ethyl xanthate with precious metals
… been studied and compared with those of ethyl xanthate (EX). The modified thiol collectors include dicresyl monothiophosphate (DCMTP), dialkyl dithiophosphinate (DTPI) and monothiophosphinate (MTPI). In general, the adsorption mechanisms on silver and gold-silver alloys can be explained by the …
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Thiosemicarbazone, xanthate and dithiocarbamate single source precursors for cadmium, lead and indium sulfide nanoparticles
… oil and olive oil. Different classes of ligands (xanthates and dithiocarbamates) were investigated on their influence in the properties of the nanoparticles, in addition to the choice of capping agent and reaction temperature. Two In(III) and two Cu(II) complexes were used in this work. Very few …
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Thermodynamic and kinetic studies of galena in the presence and absence of potassium ethyl xanthate
… showing the effect of E<sub>h</sub> and pH on xanthate uptake by the galena surface have been presented for the first time. These are particularly useful because they can be directly compared to observed flotation data. The results of voltammetry, IGP and potential-step experiments suggest that …
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Life cycle assessment of the production of xanthate salts and of their application for ARD mitigation
Xanthate salts are commonly used as collectors in the mineral processing of sulphide ores. In more recent studies, xanthate has also been used in the environmental desulphurisation flotation of sulphidic mine tailings and coal waste, with a view to mitigating acid rock drainage (ARD) risks through …
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Rate of xanthation of soda-cellulose: an investigation of the rate of xanthation of the soluble cellulose xanthate
… the rate of xanthation of the soluble cellulose xanthate, using a sodium hydroxide solution as a solvent. By this study it was hoped that further information could be obtained concerning the reaction which occurs when soda-cellulose is treated with carbon disulfide. It is concluded from the …
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Investigating the effect of water quality on the adsorption of a xanthate collector in the flotation of a sulphide ore
… concentrations of the collector sodium isobutyl xanthate (SIBX). The synthetic plant waters were prepared by adding varying concentrations of inorganic salts to distilled water in order to achieve process water compositions that reflect water compositions typically found in mining plants. …
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The effect of mixing thiol collectors in the flotation of pure sulphide ores
Using mixtures of xanthate with either dithiophosphate (DTP) or dithiocarbamate (DTC) has been reported to increase the flotation performance of several sulphide flotation operations. The increased flotation performance has often been termed synergistic. Synergism is defined as the effect exceeding …
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An electrochemical investigation on the mechanisms of interfacial interactions of a xanthate collector on PGM surfaces in the presence of ions
… in process water hinder the interaction between xanthate collectors and valuable minerals, hence, contributing to a decrease in flotation recoveries (Kirjavainen et al., 2002, Boujounoui et al., 2015). The findings in literature have been deduced without an understanding of the underlying …
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