Hydrometallurgical extraction of antimony from lead refining slags

2021 ◽  
pp. 21-25
Author(s):  
S. S. Naboychenko ◽  
А. А. Korolev ◽  
K. L. Timofeev ◽  
S. A. Krayukhin
Keyword(s):  
Processing Technique ◽  
Alkaline Solutions ◽  
Hydrometallurgical Process ◽  
Basic Slag ◽  
Oxide Melt ◽  
Metal Impurities ◽  
Lead Refining ◽  
Processing Facility ◽  
Copper Zinc ◽  
Slag Processing

Today, in order to optimize the production of copper, zinc, and lead, as well as to reduce the circulation of associated metal impurities (such as antimony, tin, bismuth and others) between the processing facilities, an ever greater attention is given to the development and implementation of processing schemes that would enable to extract associated metals and use them to produce commodities. In connection with the above, a process has been developed and tested for processing lead refining slags which include, %: 25–30 Sb, 2–10 Pb, 1–8 Sn, 3–12 As, 0.1–0.2 Cu. The resultant products included the Su-2, Su-1 and Su-0 grades of antimony or antimonous oxide. It was found that the forms in which antimony was present in the untreated slag included Sb2O3, Sb2O4, Sb2O5 and NaSb(OH)6. A hydrometallurgical process based on the use of sulphide alkaline solutions was taken as the basic slag processing technique. It is proposed to wash the slag additionally before leaching to remove arsenic from antimony, and to use the electrowinning stage to separate tin from antimony. Regimes have been identified for obtaining cathode deposits containing 96–99% Sb, with the recovery of antimony from untreated slag being 67%. The cathode deposits were refined with the help of pyrometallurgical methods and electrolysis in sulphate-fluoride media. The paper also considers the possibility of obtaining antimonous oxide by oxidizing the antimonous oxide melt and recovering Sb2O3 from exhaust gases. Based on the findings and the results of the tests, Uralelectromed is now working on designing a slag processing facility.

Case cluster of pneumoconiosis at a coal slag processing facility

2015 ◽  
Vol 58 (5) ◽  
pp. 568-576 ◽  
Author(s):  
Kathleen M. Fagan ◽  
Erin B. Cropsey ◽  
Jenna L. Armstrong
Keyword(s):  
Processing Facility ◽  
Coal Slag ◽  
Slag Processing

A New Image Processing Technique for STEM

1974 ◽  
Vol 32 ◽  
pp. 432-433
Author(s):  
Yasushi Kokubo ◽  
Hirotami Koike ◽  
Teruo Someya
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Elastic Scattering ◽  
Field Emission ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Energy Analyzer ◽  
Scanning Microscope ◽  
Scanning Electron

One of the advantages of scanning electron microscopy is the capability for processing the image contrast, i.e., the image processing technique. Crewe et al were the first to apply this technique to a field emission scanning microscope and show images of individual atoms. They obtained a contrast which depended exclusively on the atomic numbers of specimen elements (Zcontrast), by displaying the images treated with the intensity ratio of elastically scattered to inelastically scattered electrons. The elastic scattering electrons were extracted by a solid detector and inelastic scattering electrons by an energy analyzer. We noted, however, that there is a possibility of the same contrast being obtained only by using an annular-type solid detector consisting of multiple concentric detector elements.

EM of human atherosclerosis: Aortic fatty streaks with transitional lesion features

1992 ◽  
Vol 50 (1) ◽  
pp. 622-623
Author(s):  
K. Florian Klemp ◽  
J.R. Guyton
Keyword(s):  
Foam Cell ◽  
Cell Formation ◽  
Processing Technique ◽  
Foam Cell Formation ◽  
Tissue Preparation ◽  
Electron Microscopic ◽  
Extracellular Lipid ◽  
Electron Microscopic Cytochemistry ◽  
Human Atherosclerosis ◽  
Clinically Significant

The earliest distinctive lesions in human atherosclerosis are fatty streaks (FS), characterized initially by lipid-laden foam cell formation. Fibrous plaques (FP), the clinically significant lesions, differ from FS in several respects. In addition to foam cells, the FP also exhibit fibromuscular proliferation and a necrotic core region rich in extracellular lipid. The possible transition of FS into mature FP has long been debated, however. A subset of FS described by Katz etal., was intermediate in lipid composition between ordinary FS and FP. We investigated this hypothesis by electron microscopic cytochemistry by employing a tissue processing technique previously described by our laboratory. Osmium-tannic acid-paraphenylenediamine (OTAP) tissue preparation enabled ultrastructural analysis of lipid deposits to discern features characteristic of mature fibrous plaques.

Characterization of microwave-sintered ceramic composites

1993 ◽  
Vol 51 ◽  
pp. 1136-1137
Author(s):  
X. Zhang ◽  
Y. Pan ◽  
T.T. Meek
Keyword(s):  
Matrix Material ◽  
Maximum Output Power ◽  
Ceramic Matrix Composite ◽  
Ceramic Composites ◽  
Processing Technique ◽  
Structure Characterization ◽  
Alumina Powder ◽  
Maximum Output ◽  
Sintered Ceramic

Industrial microwave heating technology has emerged as a new ceramic processing technique. The unique advantages of fast sintering, high density, and improved materials properties makes it superior in certain respects to other processing methods. This work presents the structure characterization of a microwave sintered ceramic matrix composite.Commercial α-alumina powder A-16 (Alcoa) is chosen as the matrix material, β-silicon carbide whiskers (Third Millennium Technologies, Inc.) are used as the reinforcing element. The green samples consisted of 90 vol% Al2O3 powder and 10 vol% ultrasonically-dispersed SiC whiskers. The powder mixture is blended together, and then uniaxially pressed into a cylindrical pellet under a pressure of 230 MPa, which yields a 52% green density. The sintering experiments are carried out using an industry microwave system (Gober, Model S6F) which generates microwave radiation at 2.45 GHz with a maximum output power of 6 kW. The composites are sintered at two different temperatures (1550°C and 1650°C) with various isothermal processing time intervals ranging from 10 to 20 min.

Nanostructure of semiconductor quantum dots in a borosilicate glass matrix by complementary use of HREM and AEM

1990 ◽  
Vol 48 (4) ◽  
pp. 728-729
Author(s):  
M.J. Kim ◽  
L.C. Liu ◽  
S.H. Risbud ◽  
R.W. Carpenter
Keyword(s):  
Quantum Dots ◽  
Borosilicate Glass ◽  
Glass Matrix ◽  
Optical Switching ◽  
Response Times ◽  
Fast Response ◽  
Processing Technique ◽  
Internal Stresses ◽  
Electron Hole ◽  
Spatial Dimensions

When the size of a semiconductor is reduced by an appropriate materials processing technique to a dimension less than about twice the radius of an exciton in the bulk crystal, the band like structure of the semiconductor gives way to discrete molecular orbital electronic states. Clusters of semiconductors in a size regime lower than 2R {where R is the exciton Bohr radius; e.g. 3 nm for CdS and 7.3 nm for CdTe) are called Quantum Dots (QD) because they confine optically excited electron- hole pairs (excitons) in all three spatial dimensions. Structures based on QD are of great interest because of fast response times and non-linearity in optical switching applications.In this paper we report the first HREM analysis of the size and structure of CdTe and CdS QD formed by precipitation from a modified borosilicate glass matrix. The glass melts were quenched by pouring on brass plates, and then annealed to relieve internal stresses. QD precipitate particles were formed during subsequent "striking" heat treatments above the glass crystallization temperature, which was determined by differential thermal analysis.

Sign in / Sign up

Export Citation Format

Share Document