채성기 Sungki Chae , 김현수 Hyunsoo Kim , 김상배 Sangbae Kim , 김완태 Wantae Kim

DOI: Vol.30(No.4) 137-147, 2017

Sericite is a clay mineral that has a wide applications in the industry, depending on its purity. To maintain sericite’s purity as high as possible it is necessary to remove its gangue minerals or control their contents prior to use for high value-added products and applications. In this study, the wet beneficiation of sericite by applying selective grinding and sedimentation techniques, were investigated. The ore mineral was composed mainly of sericite, quartz and calcite. Analysis showed that the content of sericite increased along with the particle size decrease, but the contents of impurity minerals as quartz and calcite were tended to decrease relatively with particle size decrease. The results of liberation tests using an attrition scrubber showed that the increase in residence time and slurry density have increased the generation of fine particles in -325 mesh size range. It was observed, however, that the contents of impurities such as quartz and calcite in such fine particles also increased during prolonged scrubbing. In the dispersed form without breaking, the yield of the recovered concentrate was 15.4 wt% and the K₂O content was 9.84 wt%, after the dispersed slurry was allowed to settle for 20 minutes. On the other hand, the concentrate yield was increased to 23.4 wt% after 10 minute attrition scrubbing and 40 minute sedimentation, while its K₂O content was decreased to 9.71 wt%. Most of final products were observed as platelet-shaped particles containing Si, Al and K which are main component of sericite.

견운모, 품위향상, 선택 분쇄, 해쇄, 침강 분리, Sericite, Beneficiation, Attrition scrubbing, Selective grinding, Sedimentation

하수현 Su Hyeon Ha , 차민경 Min Kyung Cha , 김강주 Kangjoo Kim , 김석휘 Seok-hwi Kim , 김영규 Yeongkyoo Kim

DOI: Vol.30(No.4) 149-159, 2017

We investigated the mineralogical and chemical characteristics of oyster shell as the possible substitute for the limestone used as an absorbent of SO₂ gas. The oyster shells from Taean and Tongyeong were used for the comparison with limestone and those from Boyreong and Yeosu were additionally investigated. XRD results show that all shells are composed of calcite with the exception of the myostracum layer attached to adductor muscle and ligament, which is composed of aragonite. The marine sediments as impurities exist on the surface of shells or as inclusions in the shells. Calcite is the main mineral composition of the shell of barnacle which is also one of the impurities. The oyster shell is composed of three main layers; prismatic, foliated, and chalk. The oyster shell from Tongyeong with the largest shell size, has the smallest thickness of prismatic and foliated layers which contain protein called conchiolin, whereas that from Taean with the smallest shell size has the largest prismatic and foliated layers. The sizes of those two layers of the shells from Boryeong and Yeosu are larger than that from Tongyeong but smaller than Taean. Those differences are supposed to be due to the different growth environments because the oysters from Tongyeong are cultured under the sea while those from Taean are in the tidal zone. The oyster shells generally show higher amount of sulfur and phosphorus than limestone, mainly due to the composition of protein. Some elements such as Mg show significant variations in different layers. As for trace elements, Li shows much higher amount in oyster shells than limestone, suggesting the influence of the composition of the sea water on the formation of the oyster shells.

굴 패각, 소성, 석회석, 방해석, 미세구조, Oyeter shell, calcination, limestone, calcite, microstructure

이지연 Jiyeon Lee , 이진용 Jin-yong Lee , 권기덕 Kideok D. Kwon

DOI: Vol.30(No.4) 161-172, 2017

Clay minerals play a major role in the geochemical cycles of metals in the Critical Zone, the Earth surface-layer ranging from the groundwater bottom to the tree tops. Atomistic scale research of the very fine particles can help understand the fundamental mechanisms of the important geochemical processes and possibly apply to development of hybrid nanomaterials. Molecular dynamics (MD) simulations can provide atomistic level insights into the crystal structures of clay minerals and the chemical reactivity. Classical MD simulations use a force field which is a parameter set of interatomic pair potentials. The ClayFF force field has been widely used in the MD simulations of dioctahedral clay minerals as the force field was developed mainly based on dioctahedral phyllosilicates. The ClayFF is often used also for trioctahedral mineral simulations, but disagreement exits in selection of the interatomic potential parameters, particularly for Mg atom-types of the octahedral sheet. In this study, MD simulations were performed for trioctahedral clay minerals such as brucite, lizardite, and talc, to test how the two different Mg atom types (i.e., ‘mgo’ or ‘mgh’) affect the simulation results. The structural parameters such as lattice parameters and interatomic distances were relatively insensitive to the choice of the parameter, but the vibrational power spectra of hydroxyls were more sensitive to the choice of the parameter particularly for lizardite.

삼팔면체 점토광물, 분자동역학 시뮬레이션, ClayFF, 마그네슘, 진동 파워 스펙트럼, 리자다이트, Trioctahedral clay minerals, Molecular dynamics simulations, Magnesium, vibrational power spectra, lizardite

조강희 Kanghee Cho , 최낙철 Nag-choul Choi , 김성배 Song-bae Kim , 박천영 Cheon-young Park

DOI: Vol.30(No.4) 173-178, 2017

In this study, the effect of sintering temperature and zero valent iron (ZVI) content on the physical properties of functional ceramic filter(alumina based materials) such as strength and porosity were investigated. The fabrication process of the functional ceramic filter were performed under various sintering temperature (1150℃, 1250℃) and ZVI content (10, 20, 30, 50%) conditions. With increasing the sintering temperature and ZVI content, strength was increased but porosity was decreased. The physical properties for functional ceramic filter showed that the strength and porosity were obtained under ZVI content (50%) and sintering temperature (1250℃) of 99.01 MPa and 34.5%, respectively.

세라믹 필터, 소결온도, 영가철, As, 강도, ceramic filter, sintering temperature, zero valent iron, arsenic, strength

김은경 Eunkyung Kim , 안선아 Sunah Ahn , 문성우 Seongwoo Mun , 강소영 Soyeong Kang

DOI: Vol.30(No.4) 179-186, 2017

This study investigated the mineralogical characteristics of lime mortars used in pointing of Namhansanseon Yeojang from Joseon dynasty. Polarization microscopy revealed quartz, feldspar, mica, pyroxene and opaque minerals in the lime mortars. XRD analysis also confirmed clay minerals chlorite and kaolin. As a result of particle size analysis of lime mortars, the particle size distribution was wide and size was not uniform. 60% of samples were corresponded to the sand area. The chemical components detected from XRF analysis, 8.71-11.18 % of Ca as the main component of lime and SiO₂, Al₂O₃, and Fe₂O₃ in soil minerals were main components. The lime mortars showed an endothermic peak due to decarbonization reaction of CaCO₃ at 750℃ and weight reduction rate of 10%. The microstructures were agglomerated amorphous and observed rhombohedral calcite crystals by scanning electron microscope. It is considered that the pointing of Yeojang is a mortar mixed with lime and soil. In addition the Hanbongseong Yeojang was constructed using the same materials and construction technique because the minerals composition is not different according to the Yeojang location and use.

남한산성 여장, 사춤, 석회, 모르타르, 방해석, Namhansanseong Yeojang, pointing, lime, mortar, calcite

도진영 Jin Young Do , 김정진 Jeong Jin Kim

DOI: Vol.30(No.4) 187-194, 2017

In this study, marble that consist mainly of calcite were used for applicability evaluation after treated with consolidant such as alkoxysilane series of 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08%. The position and intensity of X-ray diffraction peaks are no change and increasing trend after treated with two consolidants. The results of scanning electron microscopic analysis, morphology of rope type and homogeneous surface of platy or leaflike form observed on the marble after treated with 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08%, respectively. Brightness of surface after treated with consolidant are changing slightly dark. Shore hardness and ultrasonic velocity values show increasing after treated on the marble surface with two consolidants.

알콕시실란계 강화제, 대리암, 방해석, 쇼어경도, 초음파 속도, alkoxysilane series consolidants, marble, calcite, shore hardness, ultrasonic velocity

변현숙 Hyun Suk Byun , 김영훈 Young Hun Kim , 김정진 Jeong Jin Kim

DOI: Vol.30(No.4) 195-204, 2017

For evaluation of adsorption characteristics of heavy metals, precipitates were collected from stream bottom in the Dalseong mine. The removal of some heavy metals such as As, Cu, and Cd from aqueous solution is studied using a precipitates taken from acid mine drainage. The yellowish brown (Munsell color 8.75YR 5/10) and dark brown (Munsell color 2.5YR 3/8) precipitates that collected from the study area consist mainly of schwertmannite and goethite, respectively. The percentage removal or adsorption capacity of metals depends on the initial concentration and characteristics of adsorbent. Removal efficiency of the adsorbents shows the order for metal ions of As > Cu > Cd. The adsorption efficiency by absorbent of precipitates in low concentration metal aqueous solution were observed 67.00-85.00% for As, 26.24-29.08% for Cd, and 7.67-12.82% for Cu. As the initial concentration of metal ions was increased from 1 to 10 mg/L, adsorption amount of adsorbent increased from 0.29 to 1.29 mg/g of Cu of schwertmannite, and from 0.24 to 1.97 mg/g of goethite.

중금속, 산성광산배수, 침전물, 흡착 물질, 흡착 효율, heavy metal, acid mine drainage, precipitates, adsorbent, adsorption efficiency

이승우 Seung-Woo LEE , 원혜인 Hyein Won , 최병영 Byoung-Young Choi , 채수천 Soochun Chae , 방준환 Jun-Hwan Bang , 박권규 Kwon Gyu Park

DOI: Vol.30(No.4) 205-217, 2017

Mineral carbonation by indirect method has been studied by serpentinite as cation source. Through the carbonation of CO₂ and alkaline earth ions (calcium and magnesium) from serpentinite, the pure carbonates including MgCO₃ and CaCO₃ were synthesized. The extraction solvent used to extract magnesium (Mg) was ammonium sulfate ((NH₄)₂SO₄), and the investigated experimental factors were the concentration of (NH₄)₂SO₄, reaction temperature, and ratio of serpentinite to the extraction solvent. From this study, the Mg extraction efficiency of approximately 80 wt% was obtained under the conditions of 2 M (NH₄)₂SO₄, 300℃, and a ratio of 5 g of serpentinite/75 mL of extraction solvent. The Mg extraction efficiency was proportional to the concentration and reaction temperature. NH₃ produced from the Mg extraction of serpentinite was used as a pH swing agent for carbonation to increase the pH value. About 1.78 M of NH₃ as the form of NH₄⁺ was recovered after Mg extraction from serpentinite. And, the main step in Mg extraction process of serpentinite was estimated by geochemical modeling.

이산화탄소, 광물탄산화, 사문암, 마그네슘 추출, pH 전환, Carbon dioxide, Mineral Carbonation, Serpentinite, Mg extraction, pH swing

구효진 Hyo Jin Koo , 조현구 Hyen Goo Cho , 유찬민 Chan Min Yoo , 진영근 Young Keun Jin

DOI: Vol.30(No.4) 219-227, 2017

Manganese (Mn) nodules in the Arctic Sea have been founded in the Kara Sea and Barents Sea, but mineral and chemical compositions have been rarely investigated. In this study, mineralogical and geochemical characteristics of Mn nodules obtained during the Arctic Expedition ARA07C in northern East Siberian Sea were identified, and then genesis of Mn nodules were estimated by using these characteristics. Main manganese oxide minerals constituting the manganese nodule were buserite, birnessite, and vernadite. The Mn nodules generally represent radiated and massive texture, and the layered texture was developed restrictively. The radiated texture, main feature of the manganese nodule in the East Siberian Sea, is mainly composed of cuspate-globular microstructure. Compared with the Mn nodules in Pacific and Indian Oceans, Mn nodules of the East Siberian Sea are abundant in Mn, but Fe is too scarce. There was no difference in the chemical composition and microstructures between outer and inner part of nodule. Therefore, nodules are most likely to have only one genesis during their growth, and all of nodules indicate the diagenetic in Mn-Fe-(Cu+Ni+Co)×10 ternary diagram. It is considered that the manganese nodules in the East Siberian Sea are characterized by high Mn contents because manganese contents in the Arctic Ocean were mainly resulted from river or coastal erosion and most of them are trapped in the Arctic Ocean.

동시베리아해, 망간단괴, 산화망간광물, 방사상대, Mn, East Siberian Sea, manganese nodule, manganese oxide mineral, radiated texture