Separation of Cobalt, Nickel, and Copper from Synthetic Metallic Alloy by Selective Dissolution with Acid Solutions Containing Oxidizing Agent

Oxidation of acetylferrocene and 1,1'-diacetylferrocene with cerium(IV) sulphate has been studied in aqueous sulphuric acid solutions having the overall acidity H0 = +1 to -2. The first step in oxidation of the both ferrocene derivatives consists in a fast one-electron oxidation giving the corresponding unstable ferricenium cations. Their disappearance from the solution is connected with destruction of the sandwich molecule and further redox reactions. Complete destruction of acetylferrocene necessitates two equivalents of the oxidizing agent, the same reaction of 1,1'-diacetylferrocene proceeds by action of three equivalents of the oxidizing agent. On the basis of detailed kinetic measurements mechanism of the oxidation and destruction of the both derivatives has been suggested, and rate constants of decomposition of the sandwich molecules have been determined.

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Investigations into Recycling Zinc from Used Metal Oxide Varistors via pH Selective Leaching: Characterization, Leaching, and Residue Analysis

The Scientific World JOURNAL ◽

10.1155/2015/653219 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

Toni Gutknecht ◽

Anna Gustafsson ◽

Christer Forsgren ◽

Christian Ekberg ◽

Britt-Marie Steenari

Keyword(s):

Metal Oxide ◽

Residue Analysis ◽

Weight Percent ◽

Selective Dissolution ◽

Cobalt Nickel ◽

Current Voltage ◽

Starting Point ◽

Percent Zinc ◽

Excellent Source

Metal oxide varistors (MOVs) are a type of resistor with significantly nonlinear current-voltage characteristics commonly used in power lines to protect against overvoltages. If a proper recycling plan is developed MOVs can be an excellent source of secondary zinc because they contain over 90 weight percent zinc oxide. The oxides of antimony, bismuth, and to a lesser degree cobalt, manganese, and nickel are also present in varistors. Characterization of the MOV showed that cobalt, nickel, and manganese were not present in the varistor material at concentrations greater than one weight percent. This investigation determined whether a pH selective dissolution (leaching) process can be utilized as a starting point for hydrometallurgical recycling of the zinc in MOVs. This investigation showed it was possible to selectively leach zinc from the MOV without coleaching of bismuth and antimony by selecting a suitable pH, mainly higher than 3 for acids investigated. It was not possible to leach zinc without coleaching of manganese, cobalt, and nickel. It can be concluded from results obtained with the acids used, acetic, hydrochloric, nitric, and sulfuric, that sulfate leaching produced the most desirable results with respect to zinc leaching and it is also used extensively in industrial zinc production.

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A multistep leaching of nickel-based superalloy scrap for selective dissolution of its constituent metals in hydrochloric acid solutions

Hydrometallurgy ◽

10.1016/j.hydromet.2018.02.002 ◽

2018 ◽

Vol 176 ◽

pp. 235-242 ◽

Cited By ~ 3

Author(s):

Min-Seuk Kim ◽

Jae-Chun Lee ◽

Hyun-Sik Park ◽

Min-Ji Jun ◽

Byung-Su Kim

Keyword(s):

Hydrochloric Acid ◽

Selective Dissolution ◽

Acid Solutions ◽

Nickel Based Superalloy ◽

Hydrochloric Acid Solutions

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Formation of glycol esters from olefins in acetic acid solutions containing Pd(II) and LiXO3 as oxidizing agent

Reaction Kinetics and Catalysis Letters ◽

10.1007/bf02064821 ◽

1983 ◽

Vol 22 (1-2) ◽

pp. 139-142 ◽

Cited By ~ 7

Author(s):

N. I. Kuznetsova ◽

V. A. Likholobov ◽

Yu. I. Yermakov

Keyword(s):

Acetic Acid ◽

Acid Solutions ◽

Oxidizing Agent

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Ultrastructural localization of specific nucleoprotein fractions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081887 ◽

1978 ◽

Vol 36 (2) ◽

pp. 204-205

Author(s):

G. L. Brown

Keyword(s):

Gel Electrophoresis ◽

Mouse Liver ◽

Polyacrylamide Gel Electrophoresis ◽

Ultrastructural Localization ◽

Polyacrylamide Gel ◽

Acid Extraction ◽

Acid Solutions ◽

Low Salt ◽

Liver Nuclei ◽

Phosphate Groups

Bismuth (Bi) stains nucleoproteins (NPs) by interacting with available amino and primary phosphate groups. These two staining mechanisms are distinguishable by glutaraldehyde crosslinking (Fig. 1,2).Isolated mouse liver nuclei, extracted with salt and acid solutions, fixed in either formaldehyde (form.) or gl utaraldehyde (glut.) and stained with Bi, were viewed to determine the effect of the extractions on Bi stainina. Solubilized NPs were analyzed by SDS-polyacrylamide gel electrophoresis.Extraction with 0.14 M salt does not change the Bi staining characteristics (Fig. 3). 0.34 M salt reduces nucleolar (Nu) staining but has no effect on interchromatinic (IC) staining (Fig. 4). Proteins responsible for Nu and glut.- insensitive IC staining are removed when nuclei are extracted with 0.6 M salt (Fig. 5, 6). Low salt and acid extraction prevents Bi-Nu staining but has no effect on IC staining (Fig. 7). When nuclei are extracted with 0.6 M salt followed by low salt and acid, all Bi-staining components are removed (Fig. 8).

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Triple Fixation For Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100196 ◽

1968 ◽

Vol 26 ◽

pp. 90-91 ◽

Cited By ~ 1

Author(s):

M. A. Hayat

Keyword(s):

Electron Microscopy ◽

Endoplasmic Reticulum ◽

Electron Beam ◽

Plasma Membrane ◽

Myelin Sheath ◽

Good Deal ◽

Granular Structure ◽

Oxidizing Agent ◽

Fixation Technique ◽

Large Clusters

Potassium permanganate has been successfully employed to study membranous structures such as endoplasmic reticulum, Golgi, plastids, plasma membrane and myelin sheath. Since KMnO4 is a strong oxidizing agent, deposition of manganese or its oxides account for some of the observed contrast in the lipoprotein membranes, but a good deal of it is due to the removal of background proteins either by dehydration agents or by volatalization under the electron beam. Tissues fixed with KMnO4 exhibit somewhat granular structure because of the deposition of large clusters of stain molecules. The gross arrangement of membranes can also be modified. Since the aim of a good fixation technique is to preserve satisfactorily the cell as a whole and not the best preservation of only a small part of it, a combination of a mixture of glutaraldehyde and acrolein to obtain general preservation and KMnO4 to enhance contrast was employed to fix plant embryos, green algae and fungi.

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The Effects of Ion Implantation on the Surface Features of Inconel 600

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118333 ◽

1985 ◽

Vol 43 ◽

pp. 288-289

Author(s):

John D. Rubio

Keyword(s):

Grain Boundary ◽

Ion Implantation ◽

Nuclear Power ◽

Power Plants ◽

Surface Region ◽

Selective Dissolution ◽

Boundary Region ◽

Near Surface ◽

Inconel 600 ◽

Steam Generator Tubing

The degradation of steam generator tubing at nuclear power plants has become an important problem for the electric utilities generating nuclear power. The material used for the tubing, Inconel 600, has been found to be succeptible to intergranular attack (IGA). IGA is the selective dissolution of material along its grain boundaries. The author believes that the sensitivity of Inconel 600 to IGA can be minimized by homogenizing the near-surface region using ion implantation. The collisions between the implanted ions and the atoms in the grain boundary region would displace the atoms and thus effectively smear the grain boundary.To determine the validity of this hypothesis, an Inconel 600 sample was implanted with 100kV N2+ ions to a dose of 1x1016 ions/cm2 and electrolytically etched in a 5% Nital solution at 5V for 20 seconds. The etched sample was then examined using a JEOL JSM25S scanning electron microscope.

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