• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.131-132
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• 2005

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3156-3158
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• 2010

Stable and non-hygroscopic polystyrene supported aluminium triflate (Ps-$Al(OTf)_3$), which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for Friedel-Crafts acylation of arenes using acid chlorides in the absence of solvent under mild reaction conditions. The catalyst can be reused up to five times after simple washing with dichloromethane.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.07a
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• pp.63-66
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• 1999

MF membrane element was specially designed for water purification and VSA process which can solve the fouling problem. Especially VSA process is developed for the SK Chemical's asymmetric microfiltration hollow fiber membranes. In case of outside-to-in filtration process, MF membrane element showed the excellent flux stability caused by cleaning ability of VSA process. Simultaneous back- washing with VSA considerably enhances cleaning efficiency. Form the result, the possibility of the replacement of chemical coagulation and sand filtration process with newly developed VSA process was revealed.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.639-646
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• 2004

Metal treated activated carbons are prepared using various metals. Adsorption behaviors, morphologies, as well as antibacterial effects of metal treated samples are compared before and after solvent washing. Adsorption isotherms are used to characterize the porous structure of metal treated activated carbons before and after the solvent washing with acetone or ethyl alcohol. From these data, it is noticed that the changes in physicochemical properties of metal treated activated carbons depend on the solvents employed. Similar results are observed from BET data obtained from nitrogen adsorption isotherms. From scanning electron microscopy (SEM) studies, the changes in shape and size of metal particles are observed after the samples are washed with solvents. These changes result in different blocking effects, which, in turn, affect the adsorption behavior of metal treated activated carbons. X-ray diffraction (XRD) patterns of the samples treated with different metals are different each other. High intense sharp peaks attributed to metals are observed from silver treated samples, while the peaks are not observed from copper treated samples. To compare thermodynamic behavior of metal treated activated carbons washed with different type of solvents, differential scanning calorimetric (DSC) analysis is carried out. The analysis shows similar endothermic curves for all of the samples. Finally, antibacterial effects of metal treated activated carbon against Escherichia coli are discussed. Comparing the effects among the metals employed, highest effects are obtained from Cd, while lowest effects are obtained from Cu. Antibacterial activity becomes higher with the increase of the amount of metals treated, Optimum concentrations of metals to treat activated carbons, obtained from a shake flask test, are known to be 0.4, 0.1, and 0.6 moles for Ag, Cd, and Cu, respectively.

• The Korean Journal of Petroleum Geology
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• v.12 no.1
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• pp.9-13
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• 2006

Volcanic glass shard, which shows relatively homogeneous chemical composition in volcanic eruption materials, is used to determine ages of tephra layers and then to correlate tephra layers each other for understanding of evolution of Quaternary geomorphology. For reducing processing errors in age determination and correlation of units, amorphous glass shard should be separated carefully from soil sample through laboratory procedures such as washing, separation, and identification. Introduction of these processes in detail could be reduced errors in tephrochronology by using volcanic glass shard.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2004.04a
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• pp.199-203
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• 2004

The azo red pigments for textile printing containing amino-N-substituted benzamide derivatives as diazo components and 2-hydroxy-3-naphthoyl derivatives as coupling components were prepared. They have been printed on cotton, and the fastness, such as light, washing, dry cleaning, rubbing and heat stability was estimated. The new azo red pigments were valuable colorants in case of textile printing.

• Textile Coloration and Finishing
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• v.29 no.4
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• pp.276-283
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• 2017

The aim of this study is to develop an effective dyeing process for black color on the silk fabrics, using natural Indigo, Madder, Amur cork tree, Alder, Logwood, and Gallnut. All natural dye materials were water-extracted, concentrated, and freeze-dried. Seven different processes were carried out and the color differences(${\Delta}E$) of black color with each process from the chemical black dyed fabric were compared. The light, washing, and rubbing fastness were evaluated. The black dyeing of the silk fabrics was well carried and excellent black color was obtained in every methods. The profound black color could be obtained by the subtractive mixture of the three primary colors of red, yellow, and blue in the order of indigo(blue) - amur cork tree(yellow) - madder or lac(red). Black color was efficiently obtained by iron mordant when logwood or alder fruit was used. The color difference(${\Delta}E$) from the black color with chemical dyestuff was the lowest in the indigo - amur cork tree - lac - iron method. Light fastness and washing fastness were excellent in all dyeing processes, showing grade 5. The fastness to rubbing was excellent as shown grade 5 in the dry samples of logwood - iron process and alder fruit - iron process.

• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.55-62
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• 1998

Soils contaminated with hydrocarbons and residual metals can be effectively treated by soil washing. In developing the soil washing process several major effects for separating contaminants from coarse soils progressively improved upon combinations of mining and chemical processing approaches. The pilot-scale soils washing process consists of the four major parts : 1) abrasive scouring, 2) scrubbing action using a washwater that is sometimes augmented by surfactants or other agents, 3) rinsing, and 4) regenerating the contaminated washwater. The plant was designed based upon the treatment capacity > 5 ton/hr on site. The lumpy contaminated soil fractions first experience deagglomeration and desliming passing through a rolling mill pipe. In the second unit the attrition scrubbing module equipped with paddles uses high-energy to remove contaminants from the soils. And a final rinsing system is assembled to separate the washwater containing the contaminants and very fine soils from the washed coarse soils. For recycling the contaminated washwater passes through a washwater clarifier specifically designed for flocculation, sedimentation and gravity separation of fine as well as flotation and separation of oils from the washwater. In order to more rapidly assess the applicability of soil washing at a potential site while minimizing the expense of mobilization and operation, a mobile-type soil washing process which is self-contained upon a trailer will be further developed.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2642-2646
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• 2012

Pretreatment of spent FCC catalyst and its application in remove trace olefins in aromatics were investigated in this research. The most effective pretreatment route of spent FCC catalyst was calcining at $700^{\circ}C$ for 1 h, washing with 5% oxalic acid solution in ultrasonic reactor and dried. Treated spent FCC catalyst was modified with metal halides, then to prepare catalyst to remove trace olefins in aromatics. X-ray diffraction, Pyridine-FTIR, $N_2$ adsorption-desorption and inductively coupled plasma optical emission spectrometer (ICP-OES) were used to investigate the pretreatment process. The result showed that the performance of the treated spent FCC catalyst was much greater than that of the spent FCC catalyst, which indicted the possibility and improvement of this research.

• Membrane and Water Treatment
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• v.9 no.1
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• pp.43-51
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• 2018

Hollow fiber (HF) membranes are gaining wide interest over flat membranes due to their compaction and high area to surface volume ratio. This work addresses the fabrication of HF from polysulfone (PS) and polyethersulfone (PES) using N-methylpyrrolidone (NMP) as solvent in addition to other additives to achieve desired characteristics. The semi-pilot spinning system includes jacketed vessel, four spinneret block, coagulation and washing baths in addition to dryer and winder. Different parameters affecting dry-wet spinning phase inversion process were investigated. Dope compositions of PES, NMP and polyvinyl pyrrolidone (PVP) of varying molecular weights as additive were addressed. Some critical parameters of importance were also investigated. Those include dope flow rate, air gap, coagulation & washing baths and drying temperatures. The measured dope viscosity was in the range from 1.7 to 36.5 Pa.s. Air gap distance was adjusted from 20 to 45 cm and coagulation bath temperature from 20 to $46^{\circ}C$. The HF membranes were characterized by scanning electron microscope (SEM), atomic force microscope (AFM) and mechanical properties. Results indicated prevalence of finger like structure and average surface roughness from about 29 to 78.3 nm. Profile of stress strain characteristics revealed suitability of the fibers for downstream interventions for fabrication of thin film composite membrane. Different empirical correlations were formulated which enable deeper understanding of the interaction of the above mentioned variables. Data of pure water permeability (PWP) confirmed that the fabricated samples fall within the microfiltration (MF)-ultrafiltration (UF) range of membrane separation.