조현구 Hyen Goo Cho , 김동호 Dong Ho Kim , 구효진 Hyo Jin Koo , 엄인권 In Kwon Um , 최헌수 Hun Soo Choi

DOI: Vol.27(No.4) 169-182, 2014

government has consistently investigated the development of economic mineral deposits in the Tofua volcanic arc, Tonga since 2008 for the secure of sea floor mineral resources. We studied the composition and distribution of minerals formed by hydrothermal activity around TA 25 seamounts of the Tofua volcanic arc, Lau Basin, Tonga, using X-ray diffraction analysis, scanning electron microscopy, X-ray fluorescence spectrometry, and inductively coupled plasma atomic emission spectrometry. We used 7 core samples and 9 surface sediment samples. Barite, sphalerite, and clinoclase are present in the most volcanic vent area. Gypsum, smectite, and kaolin mineral are distributed in vent A area, chalcopyrite, pyrite, smectite, and kaolin mineral are in vent B and C area, and gypsum, chalcopyrite, pyrite, and goethite are in vent D area. From the study of clay fraction, smectite and few kaolinite are detected in the most studied area except inner part of caldera, which suggest that argillic alteration are dominant in the volcanic vent areas. Various sulfide or arsenide minerals were found in the hydrothermal vent B, C, and D. The mineralogy and geochemistry suggest higher hydrothermal activities in volcanic vent B, C, and D compared to vent A and inner caldera area. Therefore higher probabilities of massive sulfide deposits may occur in hydrothermal vent B, C, and D.

해저열수광상, TA 25 해저산, X선회절분석, 열수분출구, 황동석, 섬아연석, 스멕타이트, seafloor hydrothermal deposit, TA 25 seamount, X-ray diffraction anaylsis, hydrothermal vent, chalcopyrite, sphalerite, smectite

조강희 Kang Hee Cho , 김봉주 Bong Ju Kim , 최낙철 Nag Choul Choi , 박천영 Cheon Young Park

DOI: Vol.27(No.4) 183-196, 2014

In order to study the mineralogical characteristics of a cathodic deposition-metallic powder, electrowinning experiments were carrier out on different electrolytic solutions at varying electric distances and electric currents. Under the same experimental conditions, Cu recovery was obtained much more effectively using a sodium chloride electrolyte than with a sulfuric acid electrolyte. In XRD analysis, copper (Cu0), chalcanthite and cuprite were identified in the sulfuric acid electrolyte, while copper, nantokite and chalcanthite were observed in the sodium chloride electrolyte. In the sodium chloride electrolyte solution, increasing the electric distance and the electric current increased the Cu recovery rate, anode weight and anodic corrosion. The results of XRD analysis with non-pulverized cathodic deposition-metallic powder showed the average copper crystallite size was increased by increasing the electric current and decreasing the electric distance. It is suggested that the mass transfer was controlled with diffusion on the boundary between the electrode and the electrolytic solution due to the formation of dendrite copper.

전기분해, 전해질, Cu 회수, 결정크기, 수지상 구리, electrowinning, electrolyte, Cu recovery, crystallite size, dendritic copper

곽지영 Ji Young Kwak , 최진범 Jin Beom Choi

DOI: Vol.27(No.4) 197-206, 2014

Study area (Jikjeon-ri) is located in south end of the Hadong anorthositic rocks. And along the south-western boundary, diorite intruded the Hadong anorthosite. Ilmenite ore bodies are extended in both anorthosite and diorite. And their occurrence in the diorite are not studied yet. While no particular textures are found in the ilmenite within the anorthosite, the ilmenite within the diorite shows characteristic exsolution texture, that is, ilmenite phases are separated into rutile and Fe-oxide and the ilmenite and Fe-oxide. MnO composition in ilmenite ratios are 2.14∼3.74wt%, it has higher composition in diorite than that in anorthosite. The plagioclase composition display andesine (An28.7-42.9) in the diorite and labradorite (An57.1-72.8) in the anorthosite in composition. The exsolution of ilmenite has been developed during the cooling of partly melted ilmenite into rutile and Fe-oxides which is related to the intrusion of the diorite.

회장암, 섬록암, 티탄철석, 금홍석, 산화철, 용리조직, anorthosite, diorite, ilmenite, rutile, Fe-oxide, exsolution texture

김봉주 Bong Ju Kim , 조강희 Kang Hee Cho , 최낙철 Nag Choul Choi , 박천영 Cheon Young Park

DOI: Vol.27(No.4) 207-222, 2014

In order to recover the metallic copper powder from the mine-waste rock, heap bioleaching, Fe removal and electrowinning experiments were carried out. The results of heap leaching with the mine-waste rock sample containing 0.034% Cu showed that, the leaching rate of Cu were 61% and 62% in the bacteria leaching and sulfuric acid leaching solution, respectively. Sodium hydroxide (NaOH), hydrogen peroxide (H2O2) and calcium hydroxide (Ca(OH)2) were applied to effectively remov Fe from the heap leaching solution, and then H2O2 was selected for the most In order to prepare the electrolytic solution, H2O2 were again treated in the heap leaching, and Fe removal rates were 99% and 60%, whereas Cu removal rates were 5% and 7% in the bacteria and sulfuric acid leaching solutions, respectively. After electrowinning was examined in these leaching solution, the recovery rates of Cu were obtained 98% in bacteria and obtained 76% in the sulfuric leaching solution. The dendritic form of metallic copper powder was recovered in both leaching solutions.

더미 미생물용출, 폐-광석, Fe 제거, 전해채취, 금속구리분말, heap bioleaching, mine-waste rock, Fe removing, electrowinning, metallic copper powder

김성희 Seong Hee Kim , 이상우 Sang Woo Lee , 조현구 Hyen Goo Cho , 김영호 Young Ho Kim , 김순오 Soon Oh Kim

DOI: Vol.27(No.4) 223-234, 2014

Cyanidation method has been used to extract high-purity gold and silver in mining industry. Such mining activities have used a large amount of cyanide, and the mine wastewater contained a high level of cyanide has brought about pollution of surrounding aqueous environments. This research was initiated to study TiO2-catalytic UV-LED photo-oxidation to remove cyanide from the mine wastewater. UV lamp has been generally used as a light source in conventional photo-oxidation so far, but it shows numerous drawbacks. For this reason, this study focused on the evaluation of applicability of UV-LED as an alternative light source in cyanide photo-oxidation process. Three types of TiO2 photo-catalyst were compared in terms of performance of photo-oxidation of cyanide, and the results show that Degussa P25 was the most efficient. In addition, four types of UV-LED were tested to compare their efficiencies of cyanide photo-oxidation, and their efficacy was increased in the order of 365 nm lamp-type > 365 nm can-type > 280 nm can-type > 420 nm lamp-type. Not only did this study demonstrate that UV-LED can be used in the photo-oxidation of cyanide as an alternative light source of UV lamp, but also confirmed that the performance of photo-oxidation was significantly influenced by the type of TiO2 catalysts.

시안, 광산화, 광촉매, 광산폐수, UV-LED, 이산화티타늄, Cyanide, photo-oxidation, photo-catalyst, mine wastewater, UV-LED, titanium dioxide, TiO2

이해근 Hea Geun Lee , 차상덕 Sang Deok Cha , 김정진 Jeongjin Kim , 김영훈 Young Hun Kim

DOI: Vol.27(No.4) 235-242, 2014

Uranium can be released into the water environment from natural sources and human activities. The natural source of uranium is dominant in the Korean soil and groundwater environments. Uranium has both of radioactive and chemical toxic properties. Therefore, a drinking water contaminated with uranium has a high health risk. This study was conducted to determine the uranium concentration of water systems including small village drinking water system, groundwater for drinking water purpose, spring water, groundwater monitoring well, and emergency water suppling system. The uranium concentration was compared with domestic and other countries` standard. The contamination level was also evaluated on the basis of geological characteristics of the area. Among total 803 samples, 6 exceeded the Korean standard, 30 μg/ℓ and this was about 0.7% of the total sample. On the basis of geology, uranium concentration appeared to be increased in order of biotite granodiorite > biotite granite > gneissoid granite. The highest level of uranium was 12.4 in average.

우라늄, 먹는 물, 지하수, 방사성 독성, 모암, Uranium, drinking water, groundwater, radioactive toxicity, country rock

진미은 Mi Eun Jin , 문성우 Sung Woo Moon , 류춘길 Choon Kil Ryu , 좌용주 Yong Joo Jwa

DOI: Vol.27(No.4) 243-250, 2014

We conducted investigations into the morphological characterstics and chemical compositions of the microlites included in the obsidians from the North Korean side Baekdusan (NK) and in the obsidian artefacts from the Busan Gadeokdo prehistoric site (BG). The morphology of the microlites from the NK can be divided into three groups, and trichite-acicular and trichite-asteroidal types are predominant. On the other hand the microlites from the BG show various morphological features such as acicular, margarite, lath, and asteroidal types. Silicate microlites from the NK are mostly of Ca-pyroxene compositions (hedenbergite to augite), whereas those from the BG are mostly of biotite (annite) with small amount of clinopyroxene (ferrosilite). It is well understood that the microlites from the NK are different from those from the BG in terms of the morphology, mineral content and mineral composition. Thus the obsidian aretefacts from the Busan Gadeokdo prehistoric site seem to have no genetical relationship to the obsidians from the Baekdusan.

흑요석, 미세결정, 화학조성, 백두산, 부산 가덕도, obsidian, microlite, chemical composition, Baekdusan, Busan Gadeokdo

김대식 Dae Sik Kim , 도진영 Jin Young Do , 조현구 Hyen Goo Cho

DOI: Vol.27(No.4) 251-262, 2014

Inorganic binders were studied in order to apply a conservation material for stone monument. A pure inorganic binder and 3 species of inorganic binder which contain additives on the basis of a pure inorganic binder were selected as test samples. Through the application of inorganic binders on Geochang granite investigate their influences on stone. pH 4.0 and 5.6 acid solution, respectively were manufactured on the basis of the acidity of domestic rainfall. Alkaline water with pH 8.0 and deionized water with pH 6.85 were prepared as control group. Changes in weights of inorganic binders were not definite according to the acidity of water while weight losses in inorganic binder type were greater after reaction with the water. The compressive strengths of pure inorganic binder was largest before the test but its decrease rate were larger after reaction with the water. Water absorption rate of inorganic binders are 6.72 to 12.44 kg/m2·t1/2 after reaction with the water. Such high absorption was considered that it forced water to move deep into inorganic binder and made the components of inorganic binder dissolve. Acidities of the water of pH 4.0, 5.6, 6.85 and 8.0, respectively were changed to pH 9.0-10.0 after reaction with the inorganic binders. Ion concentrations in the water changed after reaction with the inorganic binders and Mg2+, and K+ significantly increased, dissolved from the binder. The high concentration of ions detected showed that the binder reacted with water and formed white salts with high solubility such as MgSO4 .nH2O, KNO3. Ion concentrations significantly decreased from the binder after treatment with consolidant and water repellent.

석조문화재, 백화현상, 무기질 바인더, 산성비, 강화제, 발수제, Stone Monuments, Efflorescence, Inorganic Binder, Acid Rain, Consolidant, Water Repellent

황진주 Jin Ju Hwang , 김소진 So Jin Kim , 한우림 Woo Rim Han , 한민수 Min Su Han

DOI: Vol.27(No.4) 263-270, 2014

This paper was researched that provenance of the raw material for bronze relics excavated Cheonghaejin using the distribution of lead isotope ratio based on galena ores of South Korea. Also we want to make sure that the trace elements appearing as a by-product can be used as a secondary indicator for provenance research. In the case of the galena map of the East-North Asia (Mabuchi, 1985), data are plotted in China area. Therefore it is estimated that most bronzes were produced with lead ore from China. On the other hand, the same data are plotted in the Okcheon Metamorphic Belt and Yeongnam Massif of the galena map of South Korea (KOPLID, 2012). Also the contents of Ag and Sb are available as indicator due to separate ores from similar zone in lead isotope ratio.

청동, 합금비율, 주성분, 납동위원소비, 산지, Bronze, Alloy ratio, Main component, Lead isotope, Provenance

채진웅 Jin Ung Chae , 권기덕 Kideok D Kwon

DOI: Vol.27(No.4) 271-282, 2014

The physicochemical properties of clay minerals have been investigated at the atomistic to nano scale. The microscopic studies are often challenging to perform by using experimental approaches alone. In particular, hydroxyl groups of octahedral sheets in 2:1 clay minerals have been hypothesized to impact the sorption process of metal cations; however, X-ray based techniques alone, a common tool for mineral structure examination, cannot properly test the hypothesis. The current study has examined whether computational mineralogy techniques can be applied to examine the hydroxyl structures of clay minerals. Based on quantum-mechanics and molecular-mechanics computational methods, geometry optimizations were carried out for representative dioctahedral and trioctahedral phyllosilicate minerals. Both methods well reproduced the experimental lattice parameters; however, for structural distortion occurring in the tetrahedral or octahedral sheets, molecular mechanics showed significant deviations from experimental data. The orientation angle of the hydroxyl with respect to (001) basal plane is determined by the balance of repulsion between the hydroxyl proton and Si cations of tetrahedral sites; the quantum-mechanics method predicted 25 － 26° for the angle, whereas the angle predicted by the molecular-mechanics method was much higher by 10° (i.e., 35°). These results demonstrate that computational mineralogy techniques are a reliable tool for clay mineral studies and can be used to further elucidate the roles of hydroxyls in metal sorption process.

이팔면체, 삼팔면체, 전산광물학, 수산기, 점토광물, 층상규산염 광물, 구조 뒤틀림, dioctahedral, trioctahedral, clay minerals, computational mineralogy, hydroxyl group, structural distortion, phyllosilicates

김영호 Young Ho Kim , 김순오 Soon Oh Kim

DOI: Vol.27(No.4) 283-292, 2014

Talc (Mg3Si4O10(OH)2), one of sheet silicates, is soft and has been widely used in industry. Powdered talc specimen was synthesized at the pressure of 200 MPa and temperature of 60 0℃ using external heated hydrothermal high pressure apparatus. High pressure angular dispersive X-ray diffraction (ADXRD) mode experiments were performed at the Pohang Light Source (PLS) using the symmetrical diamond anvil cell (SDAC). Compression pressure was loaded up to 11.06 GPa at room temperature. This synthetic talc shows no phase transition(s) within the present pressure limit. Based on ADXRD data, bulk modulus of talc was calculated to be 72.4 GPa using Birch-Muranghan equation of state (EOS). This value is lower than that of natural talc determined previously.

합성활석, 대칭다이아몬드 앤빌 기기, 각분산X-선회절, 버치-머내한 상태방정식, 체적탄성률, synthetic talc, SDAC, ADXRD, Birch-Murnaghan EOS, bulk modulus

이승엽 Seung Yeop Lee , 이지영 Ji Young Lee , 정종태 Jong Tae Jeong , 김경수 Kyung Su Kim

DOI: Vol.27(No.4) 293-300, 2014

The bentonite, a buffer material, is essential for the deep geological disposal of HLW (high-level radioactive waste), and it is important to know its characteristic long-term evolution in the underground environment. With an assumption that the concentration of aqueous copper ions will increase if copper-coated materials on a metal canister are corroded, we examined some characteristic ion-exchanges and cation release phenomena occurring in the bentonite clay (montmorillonite) interacted with aqueous Cu cations. During the interaction between dissolved copper and bentonite, Na rather than Ca cations in the expandable clay were preferentially replaced by Cu ions in the experiment. In addition, the Cu-exchanged montmorillonite was characterized by an asymmetric X-ray diffracted pattern with relatively collapsed interlayers compared to the raw sample. These results indicate that the gradual change of the original bentonite property may occur in a underground disposal condition. We are going to further study the characteristic chemical and mineralogical changes of the bentonite buffer to be used for the disposal site by conducting additional experiments.

고준위폐기물, 벤토나이트, 구리이온, 몬모릴로나이트, 이온교환, high-level radioactive waste, bentonite, copper ion, montmorillonite, ion-exchange

박승환 Seung Hwan Park , 김영규 Yeong Kyoo Kim

DOI: Vol.27(No.4) 301-310, 2014

To investigate the role of fault gauge in the behavior of heavy metals caused by the acid rock drainage in the area of pyrite-rich andesite, XRD, pH measurement, XRF, SEM-EDS, ICP, and sequential extraction method were used. Bed rock consists of quartz, pyrophyllite, pyrite, illite, and topaz, but the brown-colored fault gouge is composed of quartz, illite, chlorite, smectite, goethite, and cacoxenite. The mineral composition of bed rock suggests that it is heavily altered by hydrothermal activity. The concentrations of heavy metals in the bed rock are as follows, Zn > As > Cu > Pb > Cr > Ni > Cd, and those in fault gouge are As > Zn > Pb > Cr > Cu > Ni > Cd. The concentrations of the heavy metals in the fault gouge are generally higher than those in the bed rock, especially for Pb, As, and Cr, which were more than twice as those in the bed rock. It is believed that the difference in the amount of heavy metals between the bed rock and the fault gouge is mainly due to the existence of goethite which is the main mineral composition in the fault gouge and can play important role in sequestering these metals by coprecipitation and adsorption. The low pH, caused by oxidation of pyrite, also plays significant role in fixation of those metals. It is confirmed that the fractions of labile (step 1) and acid-soluble (step 2), which can be easily released into the environment, were higher in the bed rock. Those fractions were relatively low in fault gauge, suggesting that fault gauge can play important role as a sink of heavy metals to prevent those ones from being released in the area where the acid rock drainage can have an influence.

단층비지, 산성암석배수, 중금속, 침철석, 연속추출법, fault gouge, acid rock drainage, mobility of heavy metal, goethite, sequential extraction

김지은 Jee Eun Kim , 김정진 Jeong Jin Kim , 김영훈 Young Hun Kim

DOI: Vol.27(No.4) 311-320, 2014

A magnetic separation study was conducted for a soil sampled from a landfill site where steel slag had been dumped for a long time. Heavy metal concentrating effect was evaluated by analyzing heavy metal content of magnetically separated soil and passed through soil. The effect was compared between soil after soil-washing process and original landfill soil and the effect was also tested between wet condition-magnetic separation and dry condition-magnetic separation. Separated ratio was relatively higher in non-soil washed sample. The water content has no significant effect on the separation rate. The concentrating effect of Fe, Pb, Cu, and Cd were 3.2, 2.1, 12.1, 2.5, 1.5 and 17.4, 7.0, 15.7, 9.6, 7.0 respectively for non-soil washed sample and soil washed sample. We can expect a bigger volume reduction effect from soil-washed samples. The volume reduction effect was obtained from the separation in dry condition. However, when the separation ratio is too high the volume reduction effect decreases. The magnetic separation leads to a volume reduction and concentration of heavy metals into a portion of soil in case of paramagnetic particles contained soil.

중금속, 자기분리, 토양, 슬래그, 농축, heavy metal, magnetic separation, soil, slag, concentrating

한국광물학회

DOI: Vol.27(No.4) 321-322, 2014