• Transactions of the Korean hydrogen and new energy society
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• v.31 no.1
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• pp.138-143
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• 2020

Metal sulfides are good candidates for cathode materials. Especially, iron sulfides and nickel sulfides have been demonstrated to be potential electrode materials among metal sulfides due to nontoxicity and high theoretical specific capacities. Electrochemical properties (capacity, cycle life, stability etc.) of Li/iron sulfides or nickel sulfides cell were improved by methode such as coating, doping of material, and nanoization of materials etc.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.3-8
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• 2000

Chemical nature of nascent metal surfaces which is one of the important active sources for tribochemical reactions was investigated using a newly developed method. Some enhanced activities were observed. For example, organic compounds chemisorbed on nascent gold surfaces and aromatic compounds decomposed on nascent nickel surfaces resulting in hydrogen evolution. Non-polar compounds such as organic sulfides had a higher chemisorption activity on nascent steel surfaces than polar compounds such as fatty acids and phosphates. Organic sulfides reacted directly with nascent steel surfaces and the surface was covered with metal sulfides. The activity for the chemisorption of organic compounds was closely dependent on the electronic structure of metals. Although benzene chemisorbed very easily on nascent surfaces of transition metals, it did not chemisorb ell nascent surfaces of simple metals. Boundary lubricating behaviors of extreme pressure additives were explained on the bases of the chemical activities of nascent surfaces obtained in this investigation. Under mild conditions, polar compounds such as fatty acids and phosphates were effective for boundary lubrication, because surfaces are covered with oxide layers. On the other hand, sulfides were more effective under severe conditions where the oxide layers were removed and the nascent surfaces were formed.

• Resources Recycling
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• v.27 no.3
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• pp.3-7
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• 2018

Development of extractive metallurgical processes for metal sulfides has become of importance owing to the depletion of oxide ores with rich metal contents. Most of the leaching reactions of metal sulfides is electrochemical reaction and can be classified as $H_2S$, S, and ${SO_4}^{2-}$ evolution type. The acidity of leaching solution and the presence and concentration of an oxidizing agent affect the formation of reaction intermediates containing sulfur. Frost diagram of sulfuroxoanion indicates that the oxoanions with higher oxidation number are more thermodynamically stable in the presence of oxidizing agents.

• Resources Recycling
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• v.22 no.3
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• pp.91-99
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• 2013

Steel industry which has been accomplishes the base of our country economy, automobile and electronic industry are taking charge of the role, whose electroplating is important. Large amount of wastewater and various metal salts, including hazardous materials was generated from the electroplating pre-treatment, plating, washing and post-plating. Currently, the general wastewater follows in the environmental law and neutralization after controlling, sludge where the various metal is mixed reclaims below multiple regulative and trust it is controlling. The sludge which includes the gas price metal reclaims in the field and trust it controls. a reclamation price of land it is insufficient but and the control expense holds plentifully and it loses the gas price metal which is valuable. Consequently, The research regarding to recover a gas price metal actively from this waste water, it is advanced. A new method to recover valuable metals from electroplating wastewater synthesis of metal sulfides using topical methods utilizing iron oxidizing bacteria, reagent of sulfides and solvent extraction using an organic solvent, such as the development of the law to recover these metals and metal sulfides of wastewater using selective recovery have been studied. By using these wastewater treatment method under frequency above 95%, it has been obtained the valuable metal from the wastewater, where the metal ion of Fe, Cu, Zn and Ni complexes was mixed. As we discuss the wastewater, which has been discharged from electroplating process, it is important and will be applied to the resources of metal in the urban mine.

• Analytical Science and Technology
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• v.14 no.6
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• pp.530-534
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• 2001

Effect of stripping solutions on the Duolite GT-73 chelating resin for ten elements, Ag(I), Al(III), Ca(II), Cd(II), Cu(II), Fe(II), Hg(II), Mn(II), Pb(II), and Zn(II), was investigated. Relation between affinities of the metal ions and solubility products of metal sulfides was studied. The smaller the solubility product of metal sulfideis, the larger the affinitie with the ionsis. The ions which have the solubility products larger than $10^{-23}$ could be effectively desorbed with nitric acid. Complexation with chloride ion enhanced the desorption efficiencies of the ions having moderately strong affinity with the resin. The ions which have very strong affinity by the chelating resin can be desorbed by complextion with thiourea and hydrochloric acid.

• Journal of the Korean Chemical Society
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• v.11 no.1
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• pp.38-43
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• 1967

In order to explain the positive catalytic action of copper compound for the rate of leaching of zinc sulfide minerals, the electrode and redox potentials of both synthetic and natural sulfides were measured at various conditions of temperatures and pressures. The potentials of Chalcopyrite and copper sulfide were considerably higher than that of zinc sulfide, whereas lead sulfide and Galena had slightly lower potentials than that of zinc sulfide. At elevated temperatures and pressures, the same tendency was obtained. By means of comparing the calculated and measured values of potentials for sulfides, it was suggested that the electrode potentials in acid solution were generated by oxidation of sulfur ion. As a result, it was concluded that the catalytic action of copper compound in the leaching of synthetic zinc sulfide should be arised from the galvanic action between sulfides keeping intimate contact one another in which copper sulfide worked as cathodic and zinc sulfide as anodic part analogous to the metal corrosion under galvanic action.

• Journal of Electrochemical Science and Technology
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• v.15 no.1
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• pp.14-31
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• 2024

The text highlights the growing need for eco-friendly energy storage and the potential of metal-organic frameworks (MOFs) to address this demand. Despite their promise, challenges in MOF-based energy storage include stability, reproducible synthesis, cost-effectiveness, and scalability. Recent progress in supercapacitor materials, particularly over the last decade, has aimed to overcome these challenges. The review focuses on the morphological characteristics and synthesis methods of MOFs used in supercapacitors to achieve improved electrochemical performance. Various types of MOFs, including monometallic, binary, and tri-metallic compositions, as well as derivatives like hybrid nanostructures, sulfides, phosphides, and carbon composites, are explored for their energy storage potential. The review emphasizes the quest for superior electrochemical performance and stability with MOF-based materials. By analyzing recent research, the review underscores the potential of MOF-based supercapacitors to meet the increasing demands for high power and energy density solutions in the field of energy storage.

• Applied Chemistry for Engineering
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• v.5 no.6
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• pp.1078-1091
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• 1994

Thermodynamic calculations have been made from existing literature data to show that it is reasonable to expect to recover metal chlorides from the chlorination of metal sulfides with chlorine gas. The reactions between 12 metal sulfides, such as, $Ag_2S$, $As_2S_3$, CdS, CuS, $Cu_2S$, FeS, HgS, $MoS_2$, $Ni_3S_2$, PbS, $Sb_2S_3$ and chlorine gas were investigated by means of thermogravimetric method. The theorical calculation and the experimental investigation showed that chlorination of sulfide is a better alternative process for the extraction metallurgical process of sulfide ores.

• Journal of the Mineralogical Society of Korea
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• v.19 no.3 s.49
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• pp.139-151
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• 2006

Base metal sulfides occur in the Huronian sedimentary rocks that cover the Archean volcanic rocks in the Cobalt area, Ontario, Canada. They are mostly concentrated in the basal conglomerate which was formed in the pre-Huronian basin structure. Sulfide occurrence can be grouped as massive sulfide clasts in the basal and Coleman conglomerate, disseminated sulfides throughout the sediments, and disseminated sulfides near Ag-Co-Ni-As carbonate veins. Detrital mechanism can explain features such as angularity of sulfide fragments and graded bedding of dissemnated sulfides. Sulfides concentrated near carbonate veins are probably of hydrothermal origin. Nearby strata-bound type massive sulfide ore deposits and mineralized interflow units are the most probable sources for syngenetic sulfides. This is supported by the angularity of sulfide fragments, presence of massive sulfide boulders which are identical in mineralogy and texture to the strata-bound type sulfide deposits in the Archean basement, and a similar composition of sphalerite in the Archean volcanic rocks and Huronian sedimentary rocks. Some sulfide grains, especially in sandstones and argillites, were undergone recrystallization during the intrusion of the Nipissing diabase.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.82.1-82.1
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• 2008