• Journal of Conservation Science
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• v.25 no.3
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• pp.299-316
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• 2009

The Goryeo roof tiles from the Oegol site in Tangjeong, Asan are classified into three groups in color such as gray, red yellow and gray-yellow groups, respectively. While each group of tiles shows characteristic specific gravity, absorption ratio, LOI and vitrification degree, mineral content and distribution, and chemical composition are generally homogeneous among all groups of roof tiles. Also, all roof tiles and soils from the site show similar geochemical behavior of elements and clay-mineralization degree. This indicates that the soil from the site is probable to be a raw material of the roof tiles. Firing temperature of the roof tiles is estimated as 950 to $1,050^{\circ}C$ for the gray group, 800 to $900^{\circ}C$ for the red yellow group, and 900 to $950^{\circ}C$ for the gray-yellow group. In conclusion, roof tiles from the Oegol site is interpreted to be made of local clay without additive minerals, applying various firing conditions and standardized purifying process of raw clay materials.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.5
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• pp.303-311
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• 2016

From having an experimental study of physical and consolidation characteristics of soft clay in Nakdong river lower basin, we come to the conclusion as follow. Clay minerals in Nakdong river lower basin are classified into Kaolinite and Illite. Water content($W_n$) is similarly distributed in a range of 50.4% to 92.8% in Noksan and 46.6% to 99.0% in Jangyu, and liquid limit(LL) of both areas appears lower than water content. In the case of compression index, the index of jangyu is a little higher than that of Noksan because Jangyu is in a range of 0.67 to 1.94 and Noksan in a range of 0.44 to 1.5. The second compression index of Jangyu in a range of 0.027 to 0.092 is also higher than Noksan in a range of 0.024 to 0.075. As a result of regression analysis, a relation between water content and compression index is linear, and between initial void ratio and compression index is shown to $C_c=0.80e_o-0.58$. The ratio of $C_{\alpha}/C_c$ in a range of 0.03 to 0.08 expresses a wide range.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.38-43
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• 2000

This study was conducted to examine the effects of cow manure originated from the clay mineral (porphyrite, zeolite and bentonite) feeding on the growth of Zea mays GK729. CEC of the manure after bentonite, zeolite, and porphyrite feeding were 147.5, 137.0, and 114.0 cmol/Kg, respectively. These values were higher than that of non-mineral treated manure, 107.5 cmol/Kg. After 3 month growing, there was significant difference among treatment in the biomass prodcution and the content of minerals in plant tissue of Z. mays, but the physico-chemical properties of soils were not showed significant difference. For these results suggested that the clay mineral enhanced the grwoth of Z. mays according to the unknown mechanism, the further studies on the physiological changes will be needed.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.165-170
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• 1987

This study was undertaken to elucidate the behavior of herbicide bensulfuron-methyl[methyl-2-[[[[[(4,6-dimethoxy pyrimidine-2yl)amino]carbonyl]amino]sulfonyl]methyl]benzoate]in soils. Adsorption of the herbicide in soils was mainly correlated with content of organic matter and clay, and canon exchange capacity. Adsorption distribution coefficient(Kd value) in clay loam soil was greater than those in loam and sandy loam soils. The Kd value decreased in the order of zeolite, bentonite, halloysite and laziolite clay minerals. Bensulfuron-methyl moved to 3cm deep in clay loam soil and 4cm deep in sandy loam and herbicide treated layer was 0 to 2cm profile in the two soils. The decomposition rate of bensulfuron methyl varied with the soil properties. The rate was slower in sterilized soil than in nonsterilized. Addition of organic matters to the soils accelerated the decomposotion. The degradation was more rapid in 30$^{\circ}C$ soil temperature than in 20$^{\circ}C$.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.83-93
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• 2015

This study investigated genetic, mineralogical and spectral characteristics of oil shale and coal samples in Dundgobi area, Mongolia. Based the Rock/Eval and Total organic carbon (TOC) analysis, kerogen type, hydrogen quantity, thermal maturity and depositional environment were confirmed. Moreover, the mineral composition of oil shale and coal samples were analyzed by XRD and spectroscopy. The result of Rock Eval/TOC analysis revealed that the samples of Eedemt deposit are immature to mature source rocks with sufficient hydrocarbon potential, and the kerogen types were classified as Type I, Type II and Type III kerogen. On the other hand, the samples from Shine Us Khudag deposit were mature with good to very good hydrocarbon potential rocks where kengen types are defined as Type I, Type II/III and Type III kerogen. According to the carbon and sulfur contents, the depositional environment of the both sites were defined as a freshwater depositional environment. The XRD analysis revealed that the mineral composition of oil shale and coal samples were quartz, calcite, dolomite, illite, kaolinite, montmorillonite, anorthoclase, albite, microcline, orthoclase and analcime. The absorption features of oil shale samples were at 1412 nm and 1907 nm by clay minerals and water, 2206 nm by clay minerals of kaolinite and montmorillonite and 2306 nm by dolomite. It is considered that spectral characteristics on organic matter content test must be tested for oil shale exploration using remote sensing techniques.

• Korean Journal of Materials Research
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• v.2 no.1
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• pp.3-11
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• 1992

Aluminum sulfate hydrate was prepared using sulfuric acid from Ha-dong kaolin. The effects of calcination-temperature and calcination-time of kaolin, reaction-temperature and reaction-time, and sulfuric acid concentration on the formation of aluminum sulfate hydrate were investigated. The precipitation condition of aluminum sulfate hydrate from sulfuric acid solution was determined. Also, the products heat-treated at different temperatures have been investigated by X-ray diffraction, thermogravimetry, differential thermal analysis, Fourier transform infrared spectrophotometer, scanning electron microscopy, particle size distribution analysis and chemical analysis. In the optimum condition, the conversion of aluminum oxide in kaolin to aluminum sulfate hydrate was 60%. From the results of XRD, TG-DTA, and FT-IR, it is suggested that the aluminum sulfate hydrate is thermally decomposed as follows ; $Al_2(SO_4)_3{\cdot}18H_2O{\rightarrow}Al_2(SO_4)_3{\cdot}6H_2O{\rightarrow}Al_2(SO_4){\rightarrow}\;amorphous\;alumina{\rightarrow}{\gamma}-alumina{\rightarrow}{\delta}-alumina{\rightarrow}{\theta}-alumina{\rightarrow}{\alpha}-alumina$. The purity of alumina powder prepared by calcining aluminum sulfate hydrate at $1200^{\circ}C$ was 99.99 percent.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.231-239
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• 2005

This study was performed to investigate adsorption characteristics of MTBE and Cd depending upon types of clay minerals md their physicochemical properties. The adsorption characteristics were examined by batch adsorption test on various experimental parameters such as adsorption time, ratio of solution to soil, concentration of contaminants, content of organic matter, pH, and zeta potential. The adsorption efficiency of MTBE or Cd for three types of clays decreased in response to the increase of the ratio of solution to soil whereas their adsorbed amounts increased. MTBE was greatly adsorbed in the decreasing order of vermiculite, bentonite, and CTAB-bentonite while Cd was adsorbed in the decreasing order of bentonite, vermiculite, and CTA-bentonite. An equilibrium isotherm for MTBE was well fitted to Freundlich plotting whereas that for Cd was closely corresponded to Langmuir isotherm. The adsorbed amount of MTBE on bentonite and vermiculite showed the maximum at 1% and 5% of humic acid, thereafter diminished while the adsorbed amount of MTBE on CTAB-bentonite increased in proportion to humic acid. Conversely, the adsorbed amount of Cd on the addition of humic acid continued to increase regardless of types of adsorbents. For all types of adsorbents, adsorbed quantity and adsorption efficiency of Cd have been coincidently increased at pH 8 and they were further enhanced at pH 10 showing 90% adsorption efficiency. Upon pH rose, the zeta potential on each adsorbent began to decrease, while increasing Cd concentration led to decline of zeta potential, which in turn ascribed to lowering dispersion stability that could consequently enhance adsorption capability.

• The Journal of Engineering Geology
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• v.33 no.1
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• pp.61-68
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• 2023

This study analyzed and compared the physicochemical characteristics of topsoil and subsoil of Grade 1 soil from an igneous rock area on the ecological and nature map. The water content and pH of the collected soil samples were measured, and X-ray fluorescence and X-ray diffraction analyses were performed. The results showed that the water content of the topsoil was higher than that of the subsoil, and its pH was more acidic than that of the subsoil. According to the X-ray fluorescence analysis results, sample I9 was closest to kaolinite, while sample I7 was most distant from kaolinite. All other samples were located between samples I7 and I9. The X-ray diffraction analysis showed that the average content of clay minerals was higher in the topsoil than in the subsoil. The most notable clay minerals produced included illite, vermiculite, kaolinite, chlorite, and gibbsite. The results of this study will be used as a basic data for topsoil restoration to convert subsoil into topsoil.

• The Journal of Engineering Geology
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• v.7 no.2
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• pp.127-137
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• 1997

Bentonites that are used currently for the civil engineering puppose in our country were investigated to reveal their physico-chemical properties such as viscosity, swelling volume, cation exchange capacity (CEC) and chemical composition, and to compare the content of their constituting minerals and their characteristics using the X-ray diffraction and infrared spectrum methods. The content of montmorillonite in the hentonites ranges from 50 to 79%. As the content of montmorillonite in the hentonites increases, the viscosity, swelling volume, water content, methylene blue adsorption, CEC, and the amount of clay-size particles tend to increase in general. Because these properties also show good correlation within them, the results can he used to infer the characteristics of hentonites indirectly. However, a few samples do not show this correlation hetween the properties. This is probably due to the characteristics of constituting minerals of raw ore and manufacturing process. A saraple with lowest content of rnontrnofiiionite was shown to be inferior in the physico-chemical properties that are needed for the civil engineering-purpose bentonites.

• Resources Recycling
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• v.19 no.3
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• pp.9-15
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• 2010

Domestic gold mine tailings, generally, contain a lot of non-metallic silica and clay minerals. These minerals can be separated from the tailings by various physical separation methods and used as raw materials for cements and ceramic products. In these physical separation procedures, metallic complex sulfides, in which Au and metallic constituents such as Pb, As and Fe were concentrated, were obtained as a by-product. These metallic constituents should be removed or separated from the by-product to extract Au efficiently. In this work, removal and separation processes of Pb, As, and Fe from the by-product were investigated. Pb was removed to under 3% by using alkaline oxidative leaching at the leaching condition of $120^{\circ}C$, 2M NaOH, 100psi $Po_2$, 250r.p.m., 4 wt.% solid and 30 min. leaching time. The leached residue was roasted and separated magnetically to obtain a non-magnetic product contained <0.2% As, <3% Fe and high concentrated Au more than 8,000 ppm.