Download or read book Effect of Impurities and Additives on the Electrowinning of Zinc written by Harold H. Fukubayashi and published by . This book was released on 1974 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Impurities and Additives on the Electrowinning of Zinc written by Harold H. Fukubayashi and published by . This book was released on 1974 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Impurities and Additives on the Electrowinning of Zinc written by Haruhisa Fukubayashi and published by . This book was released on 1972 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The effect of various impurities, commonly found in zinc electro-winning solutions, on the surface morphology of deposited zinc was investigated. Individual additions of the impurities Al, Ag, Cd, Co, Cr, Cu, Ge, Mn, Ni, Sb, Sn, Ti, PbO2, PbSO4, and HCl were studied. In a few cases additives of animal glue, gum arabic, and Na2SiO3, were used individually or in combination, to determine their effect on the surface structure of the deposited zinc. Comparisons were then made with deposits from a pure electrolyte consisting of H2SO4 and Zn2, 200 and 65 g/l, respectively. The zinc was deposited on a 99.9% pure AI sheet using Pt anodes in all but a few cases. Time, temperature, current density, and impurity concentrations were also varied for a few of the impurities. The bulk of the work was conducted at 40° C and 75 A/ft2 (82 mA/cm2). Zinc was also deposited using Pb-Ag (0.75%) anodes with or without a precoated PbO2 layer, obtained by electrolyzing in a NaF solution. Pressed PbO2 anodes were also used to determine the stability of the anode under the electrolyzing conditions. The surface morphology was examined by a scanning electron microscope (SEM). X-ray diffraction techniques were used to determine crystal orientation. A non-dispersive X-ray spectrometer was used in an attempt to locate impurity concentrations on the zinc deposit when pitting or re-solution occurred. The impurities were categorized by the effect they had on current efficiency, morphology, and apparent mechanism of H2 evolution from the cathode"--Abstract, leaf ii.
Download or read book Effect of Impurities on the Electrowinning of Zinc written by Anil Kumar Govada and published by . This book was released on 1981 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrochemical Characterization of Impurities and Additives in Zinc Electrowinning written by Xuewen Tang and published by . This book was released on 1996 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Certain Impurities and Their Interactions on Zinc Electrowinning written by Donald Ralph Fosnacht and published by . This book was released on 1978 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Zinc Electrowinning written by Roberto C. Villas-Bôas and published by CYTED-CETEM. This book was released on with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive study on zinc electrowinning and the fundamentals and practices of the same, under the influence of several important industrial variables and impurities associated with the leached concentrate.
Download or read book Fundamental Study of the Role of Cathode Structure on Zinc Electrowinning written by Horacio M. Aros and published by . This book was released on 1987 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The influence of cathode macromorphology on the current efficiency of zinc electrowinning was determined. The studies have shown that surface roughness affects current efficiency during zinc electrowinning, particularly when the electrolyte contains impurities such as nickel and antimony. Current efficiency does not change with surface roughness as long as the electrolyte is sufficiently pure. Zinc deposited on smooth zinc cathodes tends to retain a more favorable structure and macromorphology, which is less sensitive to the effects caused by antimony and nickel. Glue helps to counteract the effect of the impurities; however, its presence in the electrolyte at certain combinations with other additives produces an increase in surface roughness and a dramatic decrease in current efficiency. A definite relationship was observed between the data obtained by cyclic voltammetry and the long time current efficiency tests. A statistical screening design program was conducted to determine the individual effects and interactions of temperature (35-45°C), antimony (0.02-0.06 mg/l), nickel (1-5 mg/l), glue (5-15 mg/l) and acid concentrations (175-225 g/l) on current efficiency. The results show that smooth zinc cathodes are less susceptible to impurity attack while rough deposits give consistently lower current efficiencies than smooth zinc. Under certain conditions, glue proved to be an important factor in influencing roughness evolution. The influence of cathode current distribution on current efficiency was also investigated. The effect of current density (up to 50 mA/cm2) and sulfuric acid concentration (150-250 g/l) on current efficiency was determined. The results show that low current densities (up to 10 mA/cm2) cause an increase in hydrogen evolution and an eventual dissolution of the zinc deposits. At the same operating conditions of current efficiency tests (12 hour deposition time), cyclic voltammetry tests show that the current rise measurements present a good correlation with current efficiency. Electrolytes containing antimony and glue show that, at low current densities, glue does not completely counteract the effect that antimony and high acid concentrations have on current efficiency. A proper chemical balance of the electrolyte was very critical. The experimental results have shown that surface macromorphology of the electrode was an important factor to be considered in the evaluating the efficiency of zinc electrowinning. In addition, surface macromorphology plays an important role in the interpretation of the impurity effects"--Abstract, leaves iii-iv
Download or read book The Effects of Less Commonly Encountered Impurities on Zinc Electrowinning from Industrial Acid Sulphate Electrolyte written by and published by . This book was released on 1985 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of As(III), As(V), Bi, Ga, In, Se, Te and Tl andtheir interaction with glue on the current efficiency andpolarization behaviour of zinc deposition and on the morphologyand preferred orientation of 1-h Zn deposits electrowon fromindustrial acid sulphate electrolyte have been determined.
Download or read book PbZn 2020 9th International Symposium on Lead and Zinc Processing written by A. Siegmund and published by Springer Nature. This book was released on 2020-01-24 with total page 937 pages. Available in PDF, EPUB and Kindle. Book excerpt: Established in 1970, the PbZn symposium series is considered the leading international technical forum for the lead and zinc processing industries. The PbZn 2020 volume addresses all aspects of current processing technologies for primary and secondary lead and zinc, as well as emerging technologies for both metals.
Download or read book Extraction 2018 written by Boyd R. Davis and published by Springer. This book was released on 2018-08-18 with total page 2976 pages. Available in PDF, EPUB and Kindle. Book excerpt: This three volume set presents papers from the first collaborative global metallurgy conference focused exclusively on extractive topics, including business and economic issues. Contributions examine new developments in foundational extractive metallurgy topics and techniques, and present the latest research and insights on emerging technologies and issues that are shaping the global extractive metallurgy industry. The book is organized around the following main themes: hydrometallurgy, pyrometallurgy, sulfide flotation, and extractive metallurgy markets and economics.
Download or read book Bureau of Mines Research written by and published by . This book was released on with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1975 with total page 2834 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications Cumulative Index written by United States. Superintendent of Documents and published by . This book was released on 1976 with total page 1466 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research and Development in Extractive Metallurgy 1987 written by and published by . This book was released on 1987 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1983 with total page 1368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lead Zinc 2000 written by J. E. Dutrizac and published by John Wiley & Sons. This book was released on 2013-09-12 with total page 1071 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Lead-Zinc 2000 Symposium is the fourth in the series of decennial conferences on the processing of lead and zinc; it isorganized by the Minerals, Metals and MaterialsSociety (TMS). The Symposium the culmination of over two years of work that included the preparation of the papers by the authors, as well as the refereeing, proof-reading and indexing by the editors. The proceedings volume contains sixty-four papers which cover all aspects of lead and zinc processing, including the global business trends of the metals, plant operations, new processing installations, emerging technologies and environmental considerations. The Lead-Zinc 2000 Symposium will also honor Dr. T.R.A. Davey for his many contributions to metallurgical science and the industry throughout his distinguished career.