• Membrane Journal
• /
• v.31 no.4
• /
• pp.282-292
• /
• 2021

In this work, we tested commercial organic solvent nanofiltration (OSN) membranes using both in-house dead-end and crossflow systems. Four different crosslinked polyimide Duramem (DM) OSN membranes with various MWCO (molecular weight cut off) values were tested in organic solvents such as ethanol, N,N-dimethylformamide, acetone and acetonitrile. The membranes exhibited more reliable and reproducible performance in the crossflow system, and the performance changed significantly depending in the physical properties of the testing solvent. This is due to the initial stabilization period via pressure-induced compaction phenomenon, which can be vastly different between membrane samples. Hence, to obtain reliable and reproducible results, crossflow system is the preferred choice.

• Journal of the Korean Society of Safety
• /
• v.30 no.4
• /
• pp.73-78
• /
• 2015

The autoignition temperatures(AIT) of solvent mixture is important index for the safe handling of flammable liquids which constitute the solvent mixtures. Therefore, the AITs of common pure chemical substances are widely reported, but very limited data are available for mixtures. This study, the toluene and 2-butnaol system which used mixture solution solvent was measured the AIT and ignition delay time by using ASTM E659 apparatus. The AITs of toluene and 2-butanol constituted binary system were $547^{\circ}C$ and $400^{\circ}C$, respectively. The experimental AIT of toluene and 2-butanol were a good agreement with the calculated AIT by the proposed equations with a few average absolute deviation(A.A.D.).

• Journal of the Semiconductor & Display Technology
• /
• v.14 no.4
• /
• pp.8-12
• /
• 2015

As NMP (N-Methyl-2pyrrolidone) is becoming important in many fields, the demand for it is also rising rapidly. With its chemical property of high boiling point, low vapor pressure and high water solubility, it is easy to recover it after processing. Therefore, it is increasingly needed to develop a system that effectively recovers NMP solvent. The study produced a system modeling using AMESim software before developing high purity solvent recovery (HPSR) system to recover NMP solvent. Then, it verified reliability by comparing the simulation model with the test result.

• Clean Technology
• /
• v.23 no.4
• /
• pp.357-363
• /
• 2017

In this study, the supercritical carbon dioxide ($scCO_2$)/ n-butyl acetate (n-BA) co-solvent system was employed to remove an unexposed negative photoresist (PR) from the surface of a silicon wafer. In addition, the selectivity of the $scCO_2$/n-BA co-solvent system was confirmed for the unexposed and exposed negative PR. Optimum conditions for removal of the unexposed PR were obtained from various conditions such as pressure, temperature and n-BA ratio. The n-BA was highly soluble in $scCO_2$ without cloud point and phase separation in mostly experimental conditions. However, the $scCO_2$/n-BA co-solvent was phase separated at 100 bar, above $80^{\circ}C$. The unexposed and exposed PR was swelled in $scCO_2$ solvent at all experimental conditions. The complete removal of unexposed PR was achieved from the reaction condition of 160 bar, 10 min, $40^{\circ}C$ and 75 wt% n-BA in $scCO_2$, as measured by ellipsometry. The exposed photoresist showed high stability in the $scCO_2$/n-BA co-solvent system, which indicated that the $scCO_2$/n-BA co-solvent system has high selectivity for the PR removal in photo lithograph process. The $scCO_2$/n-BA co-solvent system not only prevent swelling of exposed PR, but also provide efficient and powful performance to removal unexposed PR.

• Journal of the Korean Ceramic Society
• /
• v.43 no.10 s.293
• /
• pp.635-639
• /
• 2006

Dispersion behavior of the slurries consisted of Pb or Bi-based glass frits, which are used for the fabrication of green sheet as PDP front panel transparent dielectric, was examined in non-aqueous solvent system. Measurements of sedimentation height and viscosity were conducted to determine proper dispersion condition in the various solvent and dispersant system. Azotropic compound and ethyl acetate were used as the solvent and ammonium-type dispersant was applied to the slurries. All slurries were dispersed well in azotropic solvent system involving 20$\sim$50 vol% ethyl acetate at 2$\sim$3 wt% dispersant content. Especially, dispersion behavior was notably improved in the addition of ethyl acetate in the Bi-based frit slurry.

• Composites Research
• /
• v.35 no.1
• /
• pp.47-51
• /
• 2022

In order to efficiently control the heat generation of electronic devices, many research has been conducted on thermally conductive composite materials. In this study, milled carbon fiber was dispersed in four solvent to investigate the relationship of carbon fiber alignment according to dispersion by solvents, and carbon fiberreinforced composite material(CFRP) was manufactured using vacuum filtration. To evaluate the arrangement of CFRP the arrangement of the prepared specimen was observed under an optical microscope, and thermal conductivity was measured by Laser Flash Analysis. The Through-plane thermal conductivity of CFRP using NMP and Ethanol was 10.79 W/mK and 10.57 W/mK respectively, which were improved by 218% and 209% compared to the In-plane thermal conductivity. The high viscosity of the solvent greatly affects the shear of the fluid, and it seemed to determine the alignment of the filler.

• Journal of the Korean Chemical Society
• /
• v.14 no.2
• /
• pp.169-177
• /
• 1970

A study was made on the radioiodination of organic compounds in presence of hydrogen peroxide both in aqueous and organic solvent systems. In case of the reaction of rosebengal, Hippuran, and 5-iodo-uracil the aqueous reaction system could give high labelling yield within a relatively short reaction time. Labelling yield of average 50% could be obtained within 30 minutes of reaction sequence. In cases of organic solvent systems (D.M.S.O., D.M.F., and Dioxane) the solvent system of D.M.S.O. could give better yield for neutral organic compounds, where as D.M.F. and Dioxane gave better labelling result for acidic materials. Especially, o-iodobenzoic acid, o-iodotoluene, and pentachlorophenol could be labelled better in organic solvent system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.224-225
• /
• 2006

$BaTiO_3$ powder를 epoxy/solvent에 혼합한 슬러리와 solvent에 혼합한 슬러리의 분산 특성을 평가하기 위하여 분산제인 silane을 $BaTiO_3$ powder 표면에 코팅한 powder를 이용하여 분산실험을 진행하였다. Silane 표면 코팅 량에 따른 $BaTiO_3$ 슬러리와 $BaTiO_3$/epoxy 복합 슬러리의 분산 특성은 서로 다른 경향으로 나타남을 확인하였으며, silanae 최적 첨가량은 $BaTiO_3$/solvent 슬러리의 경우 0.3~0.5 wt%, $BaTiO_3$/epoxy/solvent 슬러리의 경우 1wt% 이상 첨가한 조건이었다. 또한 분산성 측정의 방법으로 점도 측정 방법과 함께 표면 거칠기 측정 방법의 가능성을 확인하였다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.4 no.2
• /
• pp.114-119
• /
• 2003

This study is to remove several organic pollutants from wastewater by non-dispersive membrane solvent extraction technique. The distribution coefficients of several solvents were determined and the experimental system was operated counter-currently and cocurrently with respect to the aqueous phase and solvent. In these experiments, as the flow rate of aqueous solution inclosed, due to being shortened contact time to solvent, the rate of removal of organic pollutants decreased and as the flow rate of solvent increased, the rate of removal increased. Meanwhile, the rate of removal of organic pollutants for the countercurrent flow system was higher than that for the occurrent flow system.

• Textile Coloration and Finishing
• /
• v.26 no.3
• /
• pp.209-217
• /
• 2014

Detergency and soil redeposition of wool fabric in drycleaning solvents, i.e. petroleum solvent, perchloroethylene (PCE), decamethylcyclopentasiloxane($D_5$), with commercial detergents were studied. The detergency of wool soiled cloth in drycleaning solvents without detergents were the order of PCE > petroleum solvent > $D_5$. When commercial detergents were added to the system, the detergency were greatly improved. When 1.0% water was added to solvents/commercial detergents system, the detergency of petroleum solvent and PCE improved whereas that of $D_5$ decreased. The soil redeposition prevention effects of solvents were the same order of detergency, i.e. PCE > petroleum solvent > $D_5$. When commercial detergents were added to the system, the soil redeposition changed depending on solvents and detergents. The soil redeposition in $D_5$ became higher with a commercial detergent, therefore it is important to develop appropriate detergents for $D_5$. Three silicone surfactants were tested for detergency and soil redeposition in $D_5$ to find candidate surfactants for drycleaning detergent formulations. Silicone surfactant PEG/PPG-19/19 Dimethicone was found to be the best surfactant for $D_5$ drycleaning detergents.