• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.802-808
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• 1996

Silicic acid(SA) was extracted with organic solvents from aqueous sodium silicate solutions acidified with dilute sulfuric acid. Tetrahydrofuran(THF), isopropyl alcohol and acetone were used as organic solvents. The extraction degree of Si and the removal efficiency of Na is determined according to kinds of solvent and the mixing ratios of solvent, sodium chloride and $H_2O$. Optimum conditions for the preparation of high purity SA were THF as an organic solvent, volume ratio of organic solvent/SA : 1 (organic solvent 10ml/10ml SA) and the amount of NaCl addition 2.5g/10ml SA. The extraction degree of Si and the removal efficiency of Na at that point were 86.2% and 99.95% respectively and the purity of SA was 99.96%.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1177-1179
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• 1996

A static headspace gas chromatographic (HSGC) technique was used to quantify toluene and other solvents (methanol, isopropyl alcohol, methyl ethyl ketone and ethyl acetate) in food packaging films. Comparison of retention times and coefficient variations for standard solvents showed consistent retention time and good reproducibility. Therefore, this method using static HSGC proved to be superior in rapidity and reproducibility, and is thought to be adaptable to analysis of a large number of samples. The methanol content was $N.D.\;(not\;detected){\sim}0.939\;mg/m^2$, toluene $N.D.{\sim}1.403\;mg/m^2$, melthyl ethyl ketone $N.D.{\sim}0.932\;mg/m^2$, total solvent content was $N.D.{\sim}2.433\;mg/m^2$.

• Resources Recycling
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• v.7 no.4
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• pp.35-42
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• 1998

Surface mount technology is the biggest theme in the area of deιIronic component. To miniatunze an electronic component, s such as ferrite chip inductor, the cer뼈lic wet process for green-sheet lamination and/or screen printing method through a s solvent medium system is widely used. The preparation and characterization of NiCuZn Ferrite (NCZF) shurry and the green s sheet using the water mixed binder system has been studied. The 21 vol% of NCZF slurry was prepared by a ball milling. The p polyacrylic vinyl copolymer (Mw; 60,000) was used as a binder. Th$\xi$ mixture of distilled water, isopropyl alcohol (IPA) and 2l butoxy ethanol was used as a dispersion medium. The water content of medium varied from about 40% to 80%. As the results. Thc disp$\xi$rston stability of the NCZF slurry was attributed to the free polymer rather than the electrostatic force of the particle. T The viscosity of the NCZF slurry was greatly depended on the ratio of water content in the medium.

• Membrane Journal
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• v.25 no.5
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• pp.385-390
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• 2015

To determine the pervaporation separation characteristics of IPA/water mixtures, PEI/PDMS hollow fiber membrane module commercialized by Airrane Co. was subjected to both lab and pilot tests. The flux of $0.52kg/m^2h$ and IPA concentration of 68.5% at $25^{\circ}C$ were obtained whereas the $1.368kg/m^2h$ and 61.2% were measured at $55^{\circ}C$. In order to realized the durability of the module, the long-term test (at $50^{\circ}C$) of 100 days has been conducted and as a result, the flux $1.03{\sim}1.15kg/m^2h$ and IPA concentration 61.8~62.5% were maintained with the initial values.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.4
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• pp.213-220
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• 2019

The dry cleaning effect related to the type of soil and fiber was analyzed using silicone and alcohol-based solvents(ethyl alcohol, isopropyl alcohol, acetone) that are relatively safe for the human body and environment to improve the detergency of hydrophilic soils in dry cleaning system. Based on this analysis, an effective dry cleaning method to be carried out for improving the detergency according to the type of hydrophilic soils. After dry cleaning was performed using 20 types of artificial soiled fabrics consisting of 7 types of fibers and 4 types of hydrophilic soils, the detergency was measured and the results were compared and analyzed by solvents and fiber types. The results are presented as follows; first, the detergency of hydrophilic soils using silicone solvents showed a low rate of detergency. In particular, the tannin soil showed a lower level of detergency compared to the protein soil. Second, the detergency of hydrophilic soils using silicon solvents with dry soap differed in some detergency according to the soil and fiber types. Especially, the detergency of curry soil on cotton fabric showed significant improvement. Third, the protein soil was not removed from dry cleaning using alcohol-based solvents, but the effect of dry cleaning of curry soil on both cotton and polyester fabric was substantially improved. As a result, the elimination of blood soil is more effective in silicon solvents than in alcohol-based solvents. The removal of tannin soils may improve detergency by adding dry soap to silicon solvents or by using alcohol-based solvents as alternative solvents. The use of alternative solvents such as silicon and alcohol solvents can contribute to the environmental improvement of the dry cleaning industry, which uses petroleum-based solvents. It is also expected to provide consumers with the opportunity to choose eco-friendly and efficient dry cleaning methods.

• Clean Technology
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• v.20 no.4
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• pp.375-382
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• 2014

This work investigated the plasma-catalytic decomposition of isopropyl alcohol (IPA) and the behavior of the byproduct compounds over monolith-supported metal oxide catalysts. Iron oxide ($Fe_2O_3$) or copper oxide (CuO) was loaded on a monolithic porous ${\alpha}-Al_2O_3$ support, which was placed inside the coaxial electrodes of plasma reactor. The IPA decomposition efficiency itself hardly depended on the presence and type of metal oxides because the rate of plasma-induced decomposition was so fast, but the behavior of byproduct formation was largely affected by them. The concentrations of the unwanted byproducts, including acetone, formaldehyde, acetaldehyde, methane, carbon monoxide, etc., were in order of $Fe_2O_3/{\alpha}-Al_2O_3$ < $CuO/{\alpha}-Al_2O_3$ < ${\alpha}-Al_2O_3$ from low to high. Under the condition (flow rate: $1L\;min^{-1}$; IPA concentration: 5,000 ppm; $O_2$ content: 10%; discharge power: 47 W), the selectivity towards $CO_2$ was about 40, 80 and 95% for ${\alpha}-Al_2O_3$, $CuO/{\alpha}-Al_2O_3$ and $Fe_2O_3/{\alpha}-Al_2O_3$, respectively, indicating that $Fe_2O_3/{\alpha}-Al_2O_3$ is the most effective for plasma-catalytic oxidation of IPA. Unlike plasma-alone processes in which tar-like products formed from volatile organic compounds are deposited, the present plasma-catalyst hybrid system did not exhibit such a phenomenon, thus retaining the original catalytic activity.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.309-313
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• 1990

The rates of solvolysis of trans-$[Co(N-eten)_2Cl_2)$+ (N-eten; N-ethylethylenediamine) have been investigated using spectrophotometric method in binary aqueous mixtures containing methyl alcohol, isopropyl alcohol, t-butyl alcohol, ethylene glycol and glycerol. The values of ${\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$ obtained from temperature effect on the rate constants were $80{\sim}84 kJmol^{-1}$ and $- 28{\sim} - 45 JK^{-1}mol^{-1}.$ Extrema found in the variation of the enthalpy and entropy of activation with solvent composition correlated very well with extrema in the variation of the physical properties of mixture which relate to sharp change in the solvent structure. The reaction mechanism was discussed in terms of correlation diagrams involving the exess molar Gibbs function of mixing for the binary mixtures. The behavior of this cobalt(Ⅲ) complex was compared with that of t-butyl chloride. The application of free energy cycle to the process initial state to transition state in water and in the mixture showed that the solvation of transition state had dominant effect on the rates in the mixtures. It was found that $S_N1$ character was increased with increasing the content of co-solvent in the mixture.

• Journal of The Korean Society of Clinical Toxicology
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• v.10 no.1
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• pp.15-21
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• 2012

Purpose: Toxic alcohols are responsible for accidental and suicide motivated poisonings, resulting in death or permanent sequelae for the afflicted patients. Major therapeutic modalities in these cases include treatment with alcohol dehydrogenase inhibitors and extracorporeal elimination. There have been a number of case reports of toxic alcohol intoxication in Korea. The purpose of this study was to review the clinical characteristics of patients suffering toxic alcohol intoxication. Methods: We retrospectively reviewed the medical records of patients who presented with toxic alcohol intoxication at 8 emergency departments (ED) from Jun 2005 to Nov 2011. Patients who ingested methanol, isopropyl alcohol, ethylene glycol, and other alcohols except ethanol, were included in this study. The clinical characteristics of these patients were analyzed to include anion and osmolar gap, and estimated concentration of alcohol in the body. Results: During the study period, 21 patients were identified who had ingested toxic alcohol (methanol; 12 patients, ethylene glycol; 9 patients). At ED arrival, the mean anion gap was $18.7{\pm}6.9$ and the osmolar gap was elevated in 13 patients. Oral and IV ethanol were administrated to 11 patients in order to inhibit alcohol dehydrogenase. Extracorporeal elimination procedures such as hemodialysis were performed in 9 patients. There were no fatalities, but the one patient suffered permanent blindness. Conclusion: This study found that ethylene glycol and methanol were the substances ingested which produced toxic alcohol intoxication. The patients presented with high anion gap metabolic acidosis and were typically treated with oral ethanol and hemodialysis.

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.302-308
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• 2015

Isothermal vapor liquid equilibria for the binary system of 3-methylpentane with ethylene glycol monopropyl ether ($C_3E_1$) and ethylene glycol isopropyl ether ($iC_3E_1$) were measured at 303.15, 318.15, and 333.15K. In our previous work, phase equilibria for the binary system of $C_3E_1$ mixtures were investigated according to the chain length of alkane, alcohol or those isomer. But in this study, we discussed the different effect of $C_3E_1$ and its isomer, $iC_3E_1$, on the phase equilibria. The measured systems were correlated with a Peng-Robinson equation of state (PR EOS) combined with Wong-Sandler mixing rule for the vapor phase, and NRTL, UNIQUAC, and Wilson activity coefficient models for the liquid phase. All the measured systems showed good agreement with the correlation results. And it was found that the phase equilibria showed very little difference between the $iC_3E_1$ mixture system and the $C_3E_1$ mixture system.

• Membrane Journal
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• v.12 no.3
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• pp.158-164
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• 2002

This study was carried out the fundamental experiment to investigate the pervaporation process through NaA zeolite membrane for recycling the wasted isopropyl alcohol(IPA) in semiconductor cleaning processes. The NaA zeolite membrane used showed the excellent separation performance for full range of feed concentration and at high temperature operation. At 80 in operation temperature and 90 wt% IPA in feed concentration the separation performance was obtained about $1,500 g/m^2/hr$ in the permeation flux and more than 1,000 in the separation factor. In continuous operation of dehydration of IPA the average permeation flux was obtained about $1,000 g/m^2/hr$ at 80 and 90 wt% IPA feed concentration.