• 대한화학회지
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• 제11권1호
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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.

• 자원환경지질
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• 제42권5호
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• pp.445-455
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• 2009

미생물학적 황산염 환원은 황산염을 전자수용체로 이용하는 황산염 환원 박테리아에 의해 황산염이 황화이온으로 변환되는 과정이다. 형성된 황화이온은 주변의 용존 금속 이온과 결합하여 용해도가 낮은 금속 황화물로 침전된다. 이 연구에서는 비소와 중금속으로 오염된 송천 금은광산 일대 토양을 대상으로 하여 토착 박테리아에 의한 황산염 환원을 유도함으로써 독성 원소의 원위치 고정화 기술의 효율성을 평가하였다. 왕수 분해 결과, 대상 토양 내 비소, 구리, 납의 함량은 각각 1,311 mg/kg, 146 mg/kg, 294 mg/kg 등으로 나타나 특히 비소의 오염이 심각한 상태였다. 회분식 실험 결과, 미생물학적 황산염 환원에 의하여 pH 증가, 산화환원전위 감소, 황산염 함량 감소, 비소와 구리 함량 감소 등이 관찰되었다. 이 때 가장 높은 중금속 침전 효율을 유도하는 탄소원과 황산염의 농도 범위는 각각 0.2~0.5%, 100~200 mg/L로 나타났다. 미생물학적 또는 화학적으로 황화물 침전을 유도하게 고안된 컬럼 실험 수행 결과, 비소와 구리는 두 컬럼에서 모두 98% 이상 제거되었다. 그러나 산소를 다량 포함한 용액을 주입한 후, 화학적으로 황화물 침전을 유도한 컬럼에서는 즉각적인 비소와 구리의 재용출 현상이 나타났으나, 미생물학적 황산염 환원을 유도한 컬럼에서는 침전물이 30일 이상 장기간 안정성을 보였다. 미생물학적 컬럼 내에 형성된 검은색 침전물을 분석한 결과 FeS와 CuS로 나타났으며 비소는 대부분 철 황화물에 흡착되어 있는 것으로 확인되었다.

• 자원환경지질
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• 제16권1호
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• pp.1-10
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• 1983

The Yeonhwa (I, II) and Keodo mines, neighboring in the middle part of the Taebaegsan mineral belt, contain three distinct classes of skarn deposits: the zinc-lead skarn at Yeonhwa (I, II), the iron skarn at Keodo south (Jangsan orebodies), and the copper skarn at Keodo north (78 orebodies). The present study characterizes the three classes of skarn deposits mainly in terms of skarn/ore associations examined from chemical compositional point of view, and applies existing quantitative phase diagrams to some pertinent mineral assemblages in these mines. At Yeonhwa I the Wolam I orebody shows a vertical variation in skarn minerals ranging from clinopyroxene/garnet zone on the lower levels through clinopyroxene (without garnet) zone on the intermediate levels, and finally to rhodochrosite veins on the upper levels and surface. Ore minerals, sphalerite and galena, associate most closely with the intermediate clinopyroxene zone. At Keodo, the Jangsan iron skarn hosted in quartz monzodiolite as a typical endoskarn, shows a skarn zoning, from center of orebody to outer side, magnetite zone, magnetite/garnet zone, garnet clinopyroxene zone, and clinopyroxene/epidote/plagioclase zone. The 78 copper skarn in the Hwajeol limestone indicates a zoning, from quartz porphyry side toward limestone side, orthoclase/epidote zone, epidote/clinopyroxene zone, and clinopyroxene/garnet zone; chalcopyrite and other copper sulfides tend to be in clinopyroxene/garnet zone. Mioroprobe analyses of clinopyroxenes and garnets from the various skarn zones mentioned above revealed that the Yeonhwa zinc/lead skarns are characterized by johansenitic clinopyroxene (Hd 25-78, Jo 15-23) and manganoan andraditic garnet (Ad 13-97, Sp 1-24), whereas the Jangsan iron skarn at Keodo by Mn-poor diopsidic clinopyroxene (Di 78-93, Jo 0.2-1.0) and Mn-poor grossularitic grandite (Gr 65-77, Sp 0.5-1.0). The 78 copper skarn at Keodo is characterized by Mn-poor diopsidic-salite (Di 66-91, Jo 0.2-1.1) and Mn-poor andraditic grandite(Ad 40-74, Sp 0.5-1.1). The compositional charateristics of iron, copper, and zinc-lead skarns in the Yeonhwa-Keodo mines are in good correlations with those of the foreign counterparts. Compiling a $T-XCO_2$ phase diagram for the Jangsan endoskarns, a potential upper limit of temperature of the main stage of skarn formation is estimated to be about $530^{\circ}C$, and a lower limit to be $400^{\circ}C$ or below assuming $XCO_2=0.05$ at P total=1kb. Applying a published log $fS_2$-log $fo_2$ diagram to the Keodo 78 and Yeonhwa exoskarns, it is revealed that copper sulfides and zinc-lead sulfides do not co-exist stably below log $fS_2=-4$ and log $fO_2=-23$ at $T=400^{\circ}C$ and ${\times}CO=1$ atm.

• 자원환경지질
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• 제30권4호
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• pp.379-393
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• 1997

Geology of the Zbezkazgan copper deposit in Kazhkstan is mainly composed of Permian and Carboniferous sedimenary rocks in which copper minerals are mainly contained in grey sandstone of Carboniferous age. There are 28 layers of copper ore bodies in Zbezkazgan suite. Thickness of the ore bodies ranges from one to 35 meters, grade of the crude ore ranges from 2 to 5 wt % Cu and the extension of the orebodies is 5 to 7 km. Microscopic study on specimens from the Zbezkazgan ore deposit has exposed clues to understand the origin of this deposit. Alternatively deposited grey sandstone and red sandstone are mainly composed of quartz and feldspar grains. A big difference between the grey sandstone and the red sandstone is in grain size, the former is larger than the latter. Chalcocites as main copper minerals have cemented through grain boundary. It is assumed that quartz, feldspar and copper were derived from granitoid in which copper mineralization had taken place before exposing to weathering. The chalcocites were precipitated by a sudden change of geochemical condition (Eh, pH, temperature, etc.) of fluid which had carried quartz, feldspars, copper ions and sulphate during formation of grey sandstones. The copper ions and sulphate were stable in fluid during sedimentation of oxidation environment, however, the copper ions were no more stable at the reduced environment and changed to stable forms to precipitate copper minerals by reaction of copper ions and hydrogen sulfides. This chemical precipitation of copper minerals in the sandstone attributes to the assumption of hydrothermal origin on this sedimentary origined deposit.

• 대한금속재료학회지
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• 제46권10호
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• pp.609-616
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• 2008

Conventional bake-hardenable(BH) steels should be annealed at higher temperatures because of the addition of Ti or/and Nb which forms carbides and raises recrystallization start temperature. In this study, the development of new BH steels without Ti or Nb addition has been reviewed. The new BH steels have nearly same mechanical properties as the conventional BH steels even though it is annealed at lower temperature. The steels also show smaller deviation of the mechanical properties than that of the conventional BH steels because of the conarol of solute carbon content during steel making processes. The deviation of mechanical properties in conventional BH steels is directly dependent on the deviation of solute carbon which is greatly influenced by the amount of the carbide formers in conventional BH steels. Less alloy addition in the newly developed BH steels gives economical benefits. By taking the advantage of sulfur and/or nitrogen which scarenge in Interstitial-Free or conventional BH steels, fine manganese sulfides or nano size copper sulfides were designed to precipitate, and result in refined ferrite grains. Aluminum nitrides used as a precipitation hardening element in the developed steels were also and resull in fine and well dispersed. As a result, the developed steels with less production cost and reduced deviation of mechanical properties are under commercial production. Note that the developed BH steels are registered as a brand name of MAFE(R) and/or MAF-E(R).

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.14-20
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• 2006

During the 11 year period of 1995-2005, there was about a 40% increase in the world copper demand mainly because of the Asian economic growth. In the increase, about a half was consumed by China. Most of the China's copper demand increase has been taken place over the final 5-6 years of that period. The growth is expected to continue for several years, and in 10 years or sooner the same situation is expected for India. Copper is the third metal in global demand, but its little abundance in the Earth's crust is not well recognized. From the production rate and the abundance, a copper shortage, or crisis, has a high probability than the other metals. Deep ocean mineral resources such as manganese nodules in the Clarion-Clipperton Fracture Zones, Kuroko-type massive seafloor sulfides (SMS), and cobalt-rich manganese crusts in the EEZ and the high sea areas have big potentials for the future sources. We need to re-evaluate their potentials as copper resources and other metals to realize their developments. The same situation is under progress in the hydro-carbon markets. Methane hydrates that are classified into non-conventional hydro-carbon resources have an important role as the future sources, too.

• 자원환경지질
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• 제48권6호
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• pp.525-536
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• 2015

트라피체 프로젝트는 현재 탐사단계 중 후기(Advanced exploration)단계의 프로젝트이며 안다우아일라스-야우리 광상구 연변에 나타나는 다양한 반암 광상 중 일부라고 볼 수 있다. 이 광상은 몬조나이트 반암의 관입과 관계가 있으며, 또한, 올리고세 각력 파이프와 밀접한 관계를 가지고 있는 광상이다. 광화작용은 일차 유화광물인 황철석, 황동석, 반동석 및 휘수연석으로 구성된다. 2차 유화광물인 휘동석, 코벨라이트, 다이게나이트가 산출되며 산화동으로서 공작석, 흑동석, 적동석등이 산출된다. 침출작용(lixiviation)이나 부화과정 결과로서, 광화작용은 비전형적인 누대구조를 보여주기도 한다. 각력과 반암이 나타나는 구역에서는 수직적인 누대구조를 보여주는데, 북쪽 인근에서는 침출대, 2차부화대, 전이대 및 초생광화대가 나타나고 광상의 서쪽에서는 산화대 및 혼합대가 좁게 나타난다. 광상의 추정자원은 920 Mt @ 0.41% Cu이며 한계품위는 0.15%로 산정하고 있다.

• 자원리싸이클링
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• 제24권4호
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• pp.12-21
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• 2015

일반적으로 구리제련 슬래그내 구리함량은 0.5-3.7% 혹은 그 이상의 높은 비율로 포함되어 있며, 슬래그내 구리회수에 대한 대표적인 방법으로는 부유선별, 침출 그리고 배소가 있다. 본 연구에서는 부유선별법에 의한 구리 회수방법을 검토하였으며, 잔세이트포수제를 이용한 황화부선을 수행하였다. 산성과 알칼리 조건에서 부유선별 특성을 관찰하였으며, pH 4 에서 구리회수율 50%, pH 11 에서 구리회수율 67%로 나타났으며, 특히 pH 11에서는 $100{\mu}m$ 이상의 입자가 정광으로 부유되어 회수율이 상대적으로 높게 나타나는 경향을 보였다. 슬래그 입도를 200 mesh 이하로 분쇄하여 단체분리도를 향상시켜 pH조건별 부유선별 실험을 수행한 결과, 회수율이 78 - 83%까지 향상되는 것을 확인할 수 있었다.

• 한국광물학회지
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• 제26권4호
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• pp.219-228
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• 2013

방사성 폐기물을 지하에 장기 보관하는 금속 용기에 관한 생지화학적 부식 특성을 알아보기 위해 주철과 구리로 된 금속재료를 환원조건 하에서 디설프리칸스 황산염환원미생물과 3개월간 반응시켰다. 금속재료의 화학적/광물학적 변화를 알아보기 위해 주기적으로 용존 금속이온들의 농도를 측정하였으며, 실험이 종료된 이후 금속 시편 및 표면 이차생성물들을 전자현미경을 이용하여 분석하였다. 디설프리칸스가 없는 조건에서는 금속재료의 부식이 매우 미약하였으나, 미생물이 있는 경우에는 부식이 상대적으로 컸다. 관찰된 생지화학적 부식 산물은 주로 맥키나와이트와 황화구리 같은 검은색의 금속황화물이었으며, 표면에서 쉽게 분리되거나 콜로이드화되어 부유하였다. 특히, 구리 시편의 경우 용액 상에 용존 철이 존재할 때 세균에 의한 구리 부식의 가속화가 관찰되었는데, 이는 구리 표면에 다른 종의 황화철이 성장하면서 구리 간의 결속력을 약화시켰기 때문인 것으로 보인다.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.99-102
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• 2008

Mineralogical studies of ore and alteration minerals have been conducted for the Hugo Dummett porphyry copper deposit. The Hugo Dummett porphyry copper gold deposit is located in the South Gobi region, Mongolia and currently being explored. This deposit divided into the Cu-rich Hugo Dummett South and the Cu-Au-rich Hugo Dummett North deposits. The Hugo Dummett deposits contain 1.08% copper(1.16 billion tonnes in total) and 0.23 g/t gold(Oyunchimeg et al., 2006). Copper-gold mineralization at these deposit are centered on a high-grade copper(typically>2.5%) and gold(0.5-2 g/t) zone of intense quartz stockwork veining. The high grade copper and gold zone is mainly within the Late Devonian quartz monzodiorite intrusions and augite basalt, also locally occurs in dacitic rocks. Intense quartz veining forms a lens up to 100 m wide hosted by augite basalt and partly by quartz monzodiorite. Although many explorations have been carried out, only a few scientific works were done in the Oyu Tolgoi mining area. Therefore the nature of copper-gold mineralization and orgin of the deposit is not fully understood. Copper-gold mineralization in the Hugo Dummett deposits occurs in dominantly quartz monzodiorite and minor augite basalt, dacitic rocks and locally biotite granodiorite. Chalcopyrite, pyrite, bornite, molybdenite, tennantite, tetrahedrite, enargite, sphalerite, chalcocite, covellite, eugenite, galena and gold occur as main ore minerals in the Hugo Dummett North and South deposits. These sulfides occur as: (1) a vague vein-like trail 1-3cm long and 2-3 mm wide, (2) minute, discontinuous cracks within quartz(micron scales), and (3) irregular blebs/spots(micron scales)and (4) disseminated within the sericite and plagioclase, commonly concentrated in the quartz. Sulfide minerals commonly display as a replacement, intergrown and minor exsolution texture in the both of the Hugo Dummet deposits.