• Journal of the Mineralogical Society of Korea
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• v.12 no.2
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• pp.91-95
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• 1999

• Economic and Environmental Geology
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• v.19 no.2
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• pp.109-122
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• 1986

Mn-Pb-Zn-Ag deposits of the Janggun mine are hosted in the Cambro-Ordovician Janggun limestone mostly along the contacts of the Jurassic Chunyang granite. The deposits are represented by several ore pipes and steeply dipping lenticular bodies consisting of lower Pb-Zn-Ag sulfide ores and upper manganese carbonate and oxide ores. The former consists mainly of arsenic, antimony, silver, manganese, and tin-bearing sulfides, whereas the latter are characterized by hypogene rhodochrosite, and superficial manganese oxides including todorokite, nsutite, pyrolusite, cryptomelane, birnesite and janggunite. Origin of the upper manganese ore deposits has been a controversial subject among geologists for this mine: hydrothermal metasomatic vs. syngenetic sedimentary origin. Syngenetic advocators have proposed a new sedimentary rock, rhodochrostone, which is composed mainly of rhodochrosite in mineralogy. In the present study, carbon, oxygen and sulfur isotopic compositions were analayzed obtaining results as follows: Rhodochrosite minerals, (Mn, Ca, Mg, Fe) $CO_3$, from hydrothermal veins, massive sulfide ores and replacement ores in dolomitic limestone range in isotopic value from -4.2 to -6.3‰ in ${\delta}^{13}C$(PDB) and +7.6 to +12.9‰ in ${\delta}^{18}O$(SMOW) with a mean value of -5.3‰ in ${\delta}^{13}C$ and +10.7‰ in ${\delta}^{18}O$. The rhodochrosite bearing limestone and dolomitic limestone show average isotopic values of -1.5‰ in ${\delta}^{13}C$ and +17.5‰ in ${\delta}^{18}O$, which differ from those of the rhodochrosite mentioned above. This implies that the carbon and oxygen in ore fluids and host limestone were not derived from an identical source. ${\delta}^{34}S$ values of sulfide minerals exhibit a narrow range, +2.0 to +5.0‰ and isotopic temperature appeared to be about $288{\sim}343^{\circ}C$. Calculated initial isotopic values of rhodochrosite minerals, ${\delta}^{18}O_{H_2O}=+6.6$ to +10.6‰ and ${\delta}^{13}C_{CO_2}=-4.0$ to -5.1 ‰, strongly suggest that carbonate waters should be deep seated in origin. Isotopic data of manganese oxide ores derived from hypogene rhodochrosites suggest that the oxygen of the limestone host rock rather than those of meteoric waters contribute to form manganese oxide ores above the water table.

• Journal of Soil and Groundwater Environment
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• v.13 no.3
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• pp.52-58
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• 2008

Mn-impregnated activated carbon (Mn-AC) prepared at different conditions was applied in the treatment of synthetic wastewater containing both organic and inorganic contaminants. Phenol and As(III) was used as the representative organic and inorganic contaminants, respectively. After evaluation of the physicochemical characteristic and stability of Mn-AC, oxidation of As(III) as well as adsorption of phenol by activated carbon(AC) and Mn-AC were investigated in a batch reactor. To investigate the stability of Mn-AC, dissolution of Mn from each Mn-AC was measured pH ranging from 2 to 4. Although Mn-AC was unstable at a strong acidic condition, the dissoluted Mn was below 3 ppm at pH 4. XRD analysis of Mn-AC indicated that the mineral type of the impregnated manganese was $Mn_2O_3$. From the simultaneous treatment of As(III) and phenol by AC and Mn-AC, As(III) oxidation by Mn-AC was greater than that by AC at lower pH, while the reverse order was observed at higher pH. After impregnation of Mn onto AC, 13% decrease of the surface area was observed, causing 8% reduction of phenol removal. Considering removal properties of As(III) and phenol, Mn-AC could be applied in the simultaneous treatment of wastewater contaminated with multi-contaminants.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.564-570
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• 2013

Domestic treatment facilities for acid mine drainage (AMD) mostly used a passive treatment process. But some passive treatment facility discharged high manganese concentrations because it is required high pH (>9) for abiotic oxidation of Mn(II) to Mn(IV). This study was focused on the feasibility of biological manganese treatment using the manganese-oxidizing bacteria (Pseudomonas sp. MN5) from AMD and economical application method of it. To investigate the various conditions of water quality the most part of the experiments were based on batch test. And result of it showed that maximum manganese oxidation rate were $10.4mg/L{\cdot}h$ at the pH7. We also performed small column tests in which MOB were attached to the functional polyurethane (FPU) media containing alkaline chemicals. Manganese concentration decreased 42 mg/L to below 6 mg/L. But anaerobic condition formed by excessive bacterial respiration in column resulted in increasing effluent manganese concentration.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.255-261
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• 2007

The catalytic behavior of the manganese oxides was studied for the selective catalytic reduction with ammonia at a low temperature condition under $200^{\circ}C$. Outlet unreacted ammonia increases with decreasing temperature and increasing $NH_3/NOx$ mole ratio, however $NO_2$ shows an opposite result. $NO_2$ is generated by the adsorption of NO on the catalyst and the following oxidization to nitrates. Unreacted NH3 slip is not observed even at the $NH_3/NOx$ feed ratio above 1.0 due to the reaction between formed nitrates on the catalyst and adsorbed ammonia. The addition of Zr increases $NO_2$ generation, whereas the addition of CeO2 on the catalyst decreases $NO_2$ generation. Furthermore, the additon of the metal oxide induce DeNOx efficiency to reduce.

• Journal of IKEEE
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• v.23 no.4
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• pp.1175-1181
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• 2019

In this paper, we have studied the chemical mechanical polishing(CMP) characteristics of mixed abrasive silica slurry(MAS) retreated by adding of manganese oxide(MnO₂) abrasives within 1:10 diluted silica slurry. A slurry designed for optimal performance should produce high removal rates, acceptable polishing selectivity with respect to the underlying layer, low surface defects after polishing, and good slurry stability. The polishing performances of MnO₂ abrasive-added MAS are evaluated with respect to their particle size distribution, surface morphology, and CMP performances such as removal rate and non-uniformity. As an experimental result, we obtained the comparable slurry characteristics compared to original silica slurry in the view-point of high removal rate and low non-uniformity. Therefore, our proposed MnO₂-MAS can be useful to save on the high cost of slurry consumption since we used a 1:10 diluted silica slurry.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.902-905
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• 2009

축사 또는 쓰레기장에서 에서 발생되는 있는 물질인 암모니아, 아민, 메탄, 탄화수소류 등에 대한 처리를 위한 촉매 개발을 수행하였다. 암모니아를 금속산화물형태의 촉매를 사용하여 산화하였을 경우 $N_2$, NO, $NO_2$, $N_2O$가 일정 비율로 생성되게 된다. 이때의 NO, $NO_2$는 악취는 발생하지 않으나 유독성 가스이므로 이에 대한 선택성이 낮은 촉매를 선별하고 온도에 따른 활성능을 시험하여 최적의 촉매조성을 도출하였다. 다양한 산화가를 지닌 망간을 대상으로 각종 조촉매의 혼합에 따른 실험을 수행하여 최적 조성을 도출 하였다. 촉매 선별작업에서는 충전층을 사용하고, 선별된 촉매에 대하여 모노리스에 코팅하여 사용할 수 있는 모노리스형태의 반응기를 장착하여 모노리스 형태 촉매의 반응성 및 피독특성을 실험하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.153-153
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• 2023

골프장 건축 시 하부지반 구축을 위해 사용하는 잔석의 산화로 인해 중금속 용출이 발생할 수 있다. 용출된 중금속으로 인근 농업지역이 오염될 경우 인간의 식생활에 직접적인 영향을 미쳐 인체건강에 악영향을 끼칠 수 있다. 특히, 망간의 경우 식품을 통해 과다섭취할 경우 정신착란, 운동실조 등 다양한 신경학적 문제를 발생시키기 때문에 망간 오염에 대한 조사 및 관리는 필수적이다. 따라서, 본 연구는 최근 골프장이 건설된 부산시 일광 회룡리 일대 농업지역에서 망간 오염 평가를 위해 지표수, 퇴적물, 벼 작물을 채취하여 망간 농도 분석을 수행하였다. 골프장 유출조부터 시작되는 관개수로에서 지표수와 퇴적물 시료를 약 20 m 간격으로 채취하였으며, 관개수로의 구조에 따라 논을 4개의 구역(Area 1 - 4)으로 구분하여 논 토양과 벼 작물을 채취하였다. 벼 작물의 경우 뿌리, 줄기, 곡물 부분으로 나누어 채취하였으며, 퇴적물과 논 토양은 시료 내 존재하는 망간의 형태를 확인하기 위해 연속추출법을 통해 분석하였다. 분석 결과 지표수의 망간 농도는 골프장 유출조에서 하류로 갈수록 감소하는 경향을 보였으며, 하류에서의 망간농도는 상류에 비해 최대 88% 감소하였다. 퇴적물의 망간 농도는 논으로 연결되는 지점에서 20,000 mg/kg 이상의 높은 농도를 보였으며, 농업이 진행 중인 3, 5, 7월은 최대 약 25,000 mg/kg의 농도를 보였으나, 농업이 끝난 9월에는 최대 약 3,500 mg/kg으로 상대적으로 낮은 농도를 보였다. 논 토양의 망간 농도는 관개수로와 첫 번째로 연결되는 Area 1에서 1,600 mg/kg으로 측정되었으며, 이는 EPA에서 권고한 논 토양 망간 기준 1,000 mg/kg을 초과하는 농도로 확인되었다. 또한, 식물이 사용할 수 없는Residual 형태의 망간 농도는 변화가 없었으나, 식물이 사용 가능한 Acid soluble, Reducible, Oxidizable 형태의 망간 농도는 추수기 이후 80% 이상 감소하였다. 벼 작물의 곡물 망간 농도는100 - 200 mg/kg으로 USDA에서 발표한 쌀 곡물 망간 농도의 평균인 5 mg/kg보다 약 20배 이상 높게 검출되었다. 본 연구 결과를 통해 골프장 유출조로부터 발생하는 망간오염을 식별하고 주변 농업지역에 미치는 영향을 확인할 수 있었으며, 추후 골프장 운영으로 인한 환경오염에 대한 관리가 필요할 것으로 생각된다.

• 한국전기화학회:학술대회논문집
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• 2005.04a
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• pp.52-52
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• 2005

• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.619-626
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• 2009

The objective of this study was to evaluate the efficiency of Fe and Mn oxides coated granular activated carbons (FMOCGs) for the removal of arsenite and arsenate by oxidation and adsorption mechanisms using surface characterization and batch adsorption experiments. Within four manufactured adsorbents, Fe and Mn contents of FMOCG-1 was the highest (178.12 mg Fe/g and 11.25 mg Mn/g). In kinetic results, As(III) was removed by oxidation and adsorption with FMOCGs. Removal of arsenic by FMOCGs increased as pH value of the solution decreased. The adsorption isotherm results were well fitted with Langmuir isotherm. Adsorption amount of As(V) onto FMOCGs was higher than that of As(III) and the maximum adsorption capacities of FMOCGs for As(III) and As(V) were 1.38~8.44 mg/g and 2.91~9.63 mg/g, respectively.