Download or read book Quantitative Aspects of the Interaction Between Galena Xanthate and Oxygen at a PH Value of 10 written by and published by . This book was released on 1969 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: A continuous-flow contactor and ultraviolet spectrophotometry have been used to study the reaction between potassium ethyl xanthate, oxygen, and galena over periods of 20 to 30 hours. Quantitative results are presented for the reaction at a pH value of 10, but it is shown that the general features of the behaviour are the same within the range pH 8 to pH 11. Two types of reaction are observed. The first involves adsorption of the xanthate and takes place at a rate, dq/dt, that decreases exponentially with the quantity of reagent adsorbed: (dq/dt = a exp(-q/2.303 g)). The second is thought to involve reactions between the xanthate and the oxygen catalysed by the galena-xanthate surface. Its rate increases with time until it reaches a constant value, Rf. The period for which the adsorption reaction is dominant depends on pH. The presence of soluble reaction products in the reaction solutions was revealed by differential spectrophotometry. A tentative identification with the ethyl monothiocarbonate was made. When oxygen and xanthate are applied simultaneously to an unoxidized galena surface, an induction period is required before xanthate begins to react. The parameters of the adsorption-rate equation, and, therefore, the rate and extent of adsorption at any time, vary directly with the square root of partial pressure of oxygen (p) for p

Download or read book Quantitative Aspects of the Role of Oxygen in the Interaction Between Xanthate and Galena written by and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The reaction between potassium ethyl xanthate, oxygen, and galena over periods of 20 to 30 hr has been studied. Quantitative results are presented for the reaction at pH 10, but it is shown that the general features of the behaviour are the same within the range pH 8 to 11. Two types of reaction are observed. The first involves adsorption of the xanthate and takes place at a rate, dq/dt, that decreases exponentially with the quantity of reagent adsorbed. The second is thought to involve reaction between the xanthate and the oxygen catalyzed by the surface. Its rate increases with time until it reaches a constant value, Rf. A product of reaction may be ethyl monothiocarbonate. The parameters of the adsorption rate equation, and, therefore, the rate and extent of adsorption at any time, vary directly with the square root of partial pressure of oxygen (p) for p

Download or read book Interactions in the System Galena xanthate oxygen written by and published by . This book was released on 1965 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Interactions between solutions of potassium ethyl xanthate and galena have been studied. Advances in experimental technique have allowed certain deficiencies in previous work on the subject to be identified. The most important is the failure to recognize slow components of the interaction. Developments in technique also gave improved control of oxygen and oxidation processes in the system. Thus, a preliminary study of the quantitative aspects of the role of oxygen could be made. It has been shown that, within the sensitivity of the experiments, there is no reaction between xanthate and galena in the absence of oxygen. In the presence of oxygen, either in solution or as surface oxidation products, the reaction does not appear to terminate. If oxygen-containing xanthate solutions are contacted with a newly sulphided mineral surface, an induction period is observed; this is followed by a rapid abstraction of xanthate from solution, which gradually slows down but never ceases. As the surface becomes increasingly oxidized, the length of the induction period decreases and the initial rate of abstraction increases, but the behaviour of the system is otherwise unaffected. Once the surface is sufficiently oxidized, the abstraction of xanthate continues even in the absence of dissolved oxygen. The rate of abstraction of xanthate from oxygen-containing solutions appears to depend upon the oxygen concentration, the quantity of xanthate that has already been abstracted from the solution, and the time for which the solution has been in contact with the mineral. It is not certain whether all of the xanthate abstracted from the solution is adsorbed by the mineral. The treatment of the xanthated mineral with solutions of sodium sulphide failed to recover all of the abstracted reagent. An investigation into the possibility that the rate of xanthate decomposition is accelerated by the presence of the mineral gave inconclusive results. A more thorough study will be necessary before the reason for the discrepancy can be identified. A consideration of the literature on the system reveals an important anomaly, which centres on the failure of all attempts to reverse the adsorption of xanthate onto sulphide minerals. This anomaly can be explained in the light of the present work. Since previous workers have failed to detect the slower components of interactions in the system, they have been led to consider that equilibrium had been established under conditions where there was still a strong driving force in the forward direction. Therefore, it is probable that they failed to reverse the driving force in their attempts to desorb the reagent.

Download or read book A Conceptual Model for the Role of Oxygen in Xanthate Adsorption on Galena written by Edwin E. Maust and published by . This book was released on 1976 with total page 68 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 1971 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Flotation Index written by Dow Chemical Company. Great Western Division and published by . This book was released on 1970 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Review of Reactions in the Flotation System Galena xanthate oxygen written by and published by . This book was released on 1971 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The literature on the interactions between galena, xanthate and oxygen has been critically reviewed, with major emphasis on the work published after 1957. The contradictions in the literature have been pointed out and an attempt has been made to resolve them and to arrive at a picture of the best established chemistry of the interactions.

Download or read book Mining Journal Railway and Commercial Gazette written by and published by . This book was released on 1971 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Papers written by Nathaniel Arbiter and published by . This book was released on 1965 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Products of Reaction Between Galena and Aqueous Xanthate Solutions written by S. A. Allison and published by . This book was released on 1970 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Minerals Science and Engineering written by E. H. Wainwright and published by . This book was released on 1977 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Comprehensive Dissertation Index 1861 1972 Chemistry written by Xerox University Microfilms and published by . This book was released on 1973 with total page 960 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Infrared Spectroscopy Studies of a Xanthate galena System written by Ralph E. Coleman and published by . This book was released on 1966 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Conceptual Model for the Role of Oxygen in Xanthate Adsorption on Galena written by Edwin E. Maust and published by . This book was released on 1976 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Use of a Closed Recirculation Apparatus in the Study of the Galena Oxygen Xanthate System written by P. J. Harris and published by . This book was released on 1973 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Canadian Mining and Metallurgical Bulletin written by and published by . This book was released on 1928 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book South African national bibliography written by State Library (South Africa) and published by . This book was released on 1974 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: Classified list with author and title index.