• Title/Summary/Keyword: Pyrite

Search Result 351, Processing Time 0.026 seconds

A Philological Study on The Pyrite (자연동(自然銅)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Sul, Jae-Uk;Kim, Se-Jin;An, Hye-Rim;Chung, Il-Mun;Shin, Mi-Sook;Jang, Ha-Jeong;Choi, Jin-Bong
    • Herbal Formula Science
    • /
    • v.14 no.1
    • /
    • pp.82-104
    • /
    • 2006
  • Objectives: The aim of this study is to find the therapeutic meaning of the Pyrite in herbal medication. Methods: About the origin, the component, the processing the drug, the properties and tastes of drugs, the meridian tropism, the effects, the treating disease, the contraindication and the method of administration. We have researched thirty three literatures to mention the pyrite in time sequence. Results: 1. The pyrite belongs to the metallic herbs and it consists of Iron sulfide, sometimes containing small amounts of cobalt, nickel. silver, and gold. 2. The processing the drug are the tempering, the annealing with vinegar. the refining drug with water or RADIX GLYCYRRHIZAE and et cetra, and accoring to these methods, the pyrite classified into three groups - the rough pyrite, the tempered pyrite, the annealed pyrite. 3. The properties and tastes of drugs is pungent and regular. If pyrite is well refine, it is nearly safe form the metallic virulence. the meridian tropism is mainly liver meridian. 4. From old times, pyrite has come into general use to treat the injury of muscles and tendons and bone facture because it is effective on dissipating blood stasis, alleviating pain and reunion of bone, muscles and ligament. 5. When the symptom is gone, a medicine to contain pyrite must be stoped taking. Because of pyrite's effect on regulateing Gi and promoting blood flow. Conclusions: This study showed that the pyrite is useful herb to treat the injury of muscles and tendons and bone facture.

  • PDF

Studies on the Ore Mineralogy and Litho-geochemistry of the Sheba Deposit, Barberton Greenstone Belt, South Africa

  • Altigani, Mohammed Alnagashi Hassan
    • Economic and Environmental Geology
    • /
    • v.54 no.2
    • /
    • pp.213-232
    • /
    • 2021
  • Ore criteria at the Sheba Deposit indicate orogenic mineralization type. Rocks and mineral assemblages suggest low formation-temperature of green-schist facies. Pyrite found in two generations; Type1 is irregular grains, contains higher arsenic and gold contents, compared to the relatively younger phase Type2 pyrite, which is composed of euhedral grains, found adjacent to late quartz-carbonate veins or at rims of type1 pyrite. Two gold generations were identified; type1 found included in sulphides (mainly pyrite). The second gold type was remobilized (secondary) into free-lodes within silicates (mainly quartz). Gold fineness is high, as gold contains up to 95 wt. % Au, Ag up to 3.5 wt. %, and traces of Cu, Ni, and Fe. Pyrite type2 contains tiny mineral domains (rich in Al, Mn, Hg, Se, Ti, V, and Cr). Zoning, and replacement textures are common, suggesting multiple mineralization stages. The distribution and relationships of trace elements in pyrite type2 indicate three formation patterns: (1) Al, Mn, Hg, Se, Ti, V, Cr, and Sn are homogeneously distributed in pyrite, reflecting a synchronous formation. (2) As, Ni, Co, Zn, and Sb display heterogeneous distribution pattern in pyrite, which may indicate post-formation existence due to other activities. (3) Au and Ag show both distribution patterns within pyrite, suggesting that gold is found both in microscopic phases and as chemically bounded phase.

Application of Galvanic Oxidation and Pyrite Dissolution for Sustainable In-Situ Mine Tailings Treatment (갈바닉 산화와 황철석 용해를 이용한 친환경 원위치 광미 무해화 기술)

  • Ju, Won Jung;Jho, Eun Hea;Nam, Kyoungphile
    • Ecology and Resilient Infrastructure
    • /
    • v.3 no.4
    • /
    • pp.279-284
    • /
    • 2016
  • Mine tailings generated during mining activity often contain high concentrations of heavy metals, with pyrite-containing mine tailings in particular being a major cause of environmental problems in mining areas. Chemical cell technology, or fuel cell technology, can be applied to leach heavy metals in pyrite-containing mine tailings. As pyrite dissolves through spontaneous oxidation (i.e. galvanic oxidation) in the anode compartment of the cell, $Fe^{3+}$, sulfuric acid are generated. A decrease in pH due to the generation of sulfuric acid allows heavy metals to be leached from pyrite-containing mine tailings. In this study, pyrite was dissolved for 4 weeks at $23^{\circ}C$ in an acidic solution (pH 2) and in a galvanic reactor, which induces galvanic oxidation, and total Fe leached from pyrite and pH were compared in order to investigate if galvanic oxidation can facilitate pyrite oxidation. The change in the pyrite surface was analyzed using a scanning electron microscope (SEM). Comparing the total Fe leached from the pyrite, there were 2.9 times more dissolution of pyrite in the galvanic reactor than in the acidic solution, and thus pH was lower in the galvanic reactor than in the acidic solution. Through SEM analysis of the pyrite that reacted in the galvanic reactor, linear-shaped cracks were observed on the surface of the pyrite. The study results show that pyrite dissolution was facilitated through the galvanic oxidation in the galvanic reactor, and also implied that the galvanic oxidation can be one remediation option for pyrite-containing mine tailings.

Hydrated Lime Roasting of Precious Metal Ores with A Cyclone Reactor

  • Cho, Chong S.
    • Proceedings of the Korea Association of Crystal Growth Conference
    • /
    • 1997.06a
    • /
    • pp.53-60
    • /
    • 1997
  • The roasting of pyrite with a cyclone reactor have been studied in terms of investigating the reaction behavior of pyrite. The development of a fundamental model for pyrite oxidation and lime sulfation in a vertical cyclone reactor. The model assumes a chemical control shrinking core behavior for the pyrite and a fluid film control shrinking core behavior for the lime. The oxygen and sulphur dioxide concentrations and the energy balance for the gas, pyrite and lime particles are solved. The model was solved and characterized numerically. Experiments have been performed to study the influence of reaction parameters such as reactor temperatures, pyrite particle sizes, air flow rates, feeding rates, and mixing ratio of pyrite and lime. The oxidation and sulfation products were characterized chemically and physically.

  • PDF

Effects of Pyrite (FeS2) Particle Sizes on Electrochemical Characteristics of Thermal Batteries (열전지의 전기화학적 특성에 미치는 황철석(FeS2) 입자크기의 영향)

  • Choi, Yusong;Yu, Hye-Ryeon;Cheong, Haewon;Cho, Sungbaek;Lee, Young-Seak
    • Applied Chemistry for Engineering
    • /
    • v.25 no.2
    • /
    • pp.161-166
    • /
    • 2014
  • In this study, effects of pyrite ($FeS_2$) particle sizes on the electrochemical characteristics of thermal batteries are investigated using unit cells made of pulverized pyrite by ball-milling. At $450^{\circ}C$ unit cell discharge test, the electrochemical capacity of $1.46{\mu}m$ pyrite-cell largely increases compared to $98.4{\mu}m$ pyrite-cell, and their internal resistances also decrease. These results are attributed to the increase in the active reaction area of pyrite by ball milling. However, at $500^{\circ}C$ unit cell discharge test, a $1.46{\mu}m$ pyrite cell shows lower internal resistance than that of $98.4{\mu}m$ pyrite cell only at Z-phase region ($FeS_2{\rightarrow}Li_3Fe_2S_4$). After that, a $1.46{\mu}m$ pyrite cell shows a decrease in the cell voltage and an rapid increase of the internal resistance in J-phase region ($Li_3Fe_2S_4{\rightarrow}LiFe_2S_4$) is observed compared to those of $98.4{\mu}m$ pyrite cell. It can be concluded that at the higher temperature, the thermally unstable pulverized pyrite is decomposed thermally as well as self discharged, simultaneously, which causes the higher resistance and lower capacity at $500^{\circ}C$ in J-phase than that of $98.4{\mu}m$ pyrite cell.

Suppression of Pyrite Oxidation by Formation of Iron Hydroxide and Fe(III)-silicate Complex under Highly Oxidizing Condition

  • Lee, Jin-Soo;Chon, Chul-Min;Kim, Jae-Gon
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.44 no.2
    • /
    • pp.297-302
    • /
    • 2011
  • Acid drainage generated by pyrite oxidation has caused the acidification of soil and surface water, the heavy metal contamination and the corrosion of structures in abandoned mine and construction sites. The applicability of Na-acetate (Na-OAc) buffer and/or Na-silicate solution was tested for suppressing pyrite oxidation by reacting pyrite containing rock and treating solution and by analyzing solution chemistry after the reaction. A finely ground Mesozoic andesite containing 10.99% of pyrite and four types of reacting solutions were used in the applicability test: 1) $H_2O_2$, 2) $H_2O_2$ and Na-silicate, 3) $H_2O_2$ and 0.01M Na-OAc buffer at pH 6.0, and 4) $H_2O_2$, Na-silicate and 0.01M Na-OAc buffer at pH 6.0. The pH in the solution after the reaction with the andesite sample and the solutions was decreased with increasing the initial $H_2O_2$ concentration but the concentrations of Fe and $SO_4^{2-}$ were increased 10 - 20 times. However, the pH of the solution after the reaction increased and the concentrations of Fe and $SO_4^{2-}$ decreased in the presence of Na-acetate buffer and with increasing Na-silicate concentration at the same $H_2O_2$ concentration. The solution chemistry indicates that Na-OAc buffer and Na-silicate suppress the oxidation of pyrite due to the formation of Fe-hydroxide and Fe-silicate complex and their coating on the pyrite surface. The effect of Na-OAc buffer and Na-silicate on reduction of pyrite oxidation was also confirmed with the surface examination of pyrite using scanning electron microscopy (SEM). The result of this study implies that the treatment of pyrite containing material with the Na-OAc buffer and Na-silicate solution reduces the generation of acid drainage.

On the preparation of iron pyrite from synthetic and natural targets by pulsed electron deposition

  • Al-Shareeda, Omar;Henda, Redhouane;Pratt, Allan;McDonald, Andrew M.
    • Advances in nano research
    • /
    • v.1 no.4
    • /
    • pp.219-228
    • /
    • 2013
  • We report on the preparation of iron pyrite ($FeS_2$) using pulsed electron ablation of two targets, namely, a mixture of sulfur and iron compound target, and a natural iron pyrite target. Thin films of around 50 nm in thickness have been deposited on glass substrates under Argon background gas at 3 mTorr, and at a substrate temperature of up to $450^{\circ}C$. The thin films have been analyzed chemically and examined structurally using x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and visible Raman spectroscopy. The morphology and thickness of the films have been assessed using scanning electron microscopy (SEM) and visible spectroscopic reflectance. The preliminary findings, using a synthetic target, show the presence of iron pyrite with increasing proportion as substrate temperature is increased from $150^{\circ}C$ to $250^{\circ}C$. The data have not shown any evidence of pyrite in the deposited films from a natural target.

A kinetic study of pyrite in the lime roasting of a vertical cyclone (수직 싸이클론의 ${Ca(OH)}_{2}$ 배소에서 $FeS_{2}$의 열적반응에 관한 연구)

  • 조종상
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.9 no.1
    • /
    • pp.119-125
    • /
    • 1999
  • This research has been studied in terms of investigating the reaction behavior of pyrite with a cyclone reactor. The Mathematical model has developed pyrite oxidation and lime sulfation in this reactor. The model assumes a chemical control shrinking core behavior for the pyrite and a fluid film control shrinking core behavior for the lime. The model was solved and characterized numerically. Experiments have been performed to study the influence of reaction parameters such as reactor temperatures, pyrite particle sizes, air flow rates, feeding rates, and mixing ratio of pyrite and lime. The oxidation and sulfation products were characterized chemically and physically.

  • PDF

Variation of Characteristics on the Surface of Pyrite as Microbial Leaching by Thiobacillus ferrooxidans Progresses (Thiobacillus ferrooxidans에 의한 Pyrite의 생물학적 침출에 따른 기질 표면 특성변화)

  • 이인화;박천영
    • KSBB Journal
    • /
    • v.16 no.3
    • /
    • pp.295-301
    • /
    • 2001
  • The leaching effect of Thiobacillus ferrooxidance (ATCC 19859) upon polished pyrite ore in 9K medium at $30^{circ}C$ for 30 days was investigated. The surface atomic ratios for Fe, S, Al, Si, and Cu were analyzed by EPMA using fresh and leached samples. The atomic ratio of Fe and S were changed to Fe rich phase as leaching progressed over 13 days but the Fe/S ratio became constant between 13 and 30 days. SEM imaging showed that $10\mum$ oblong shapes formed on the surface after 13 days and that these further developed until 23 days. Fe, S and K atomic ratios were analyzed by SEM-EDS.

  • PDF

Rapid climate change during the deglaciation of Lake Hovsgol, Mongolia

  • Chun, Jong-Hwa;Cheong, Dae-Kyo
    • Proceedings of the Korean Quaternary Association Conference
    • /
    • 2005.10a
    • /
    • pp.34-39
    • /
    • 2005
  • A 120-cm core recovered from Lake Hovsgol, the northern Mongolia provides evidence for climate variability since the Marine Isotope Stage 3, representing a sharp lithological change. The lowermost part of the core consists of diatom-barren calcareous silty clay without coarse sands, framboidal pyrite, and biogenic components deposited during the MIS 3. Following the last glacial maximum, in-situ moss is included in the sediments, as lake-level was retreated by cold and dry environment with low precipitation. The AMS radiocarbon ages of the plant fragments match a marked lithologic boundary between 14,060 and 14,325 $^{14}C$ yr BP. The contents of coarse sands abruptly increase, indicating probably wind-derived sandy dust or coarse grains contributed from floating icebergs. And abundant framboidal pyrite grains were deposited in an anoxic environment, as reflected by high accumulation of organic matters at a low lake stand. During the deglaciation, quantities of coarse sands, ostracod, shell fragments, framboidal pyrite, and diatom markedly varies by regional and global scale climate regimes. Some allochthonous coarse sands were probably ice-rafted debris derived from floating icebergs. A rapid increase in diatom productivity probably marked the onset of Bolling-Allerodwarming. Subsequent high concentration of framboidal pyrite probably represents a dry and cold condition, such as Younger Drays events. Consistent warm period with high precipitation at Holocene is documented by diatomaceous clayey ooze without framboidal pyrite, coarse sands, and ostracod.

  • PDF