가변 부피 view cell을 이용한 메탄올/CO₂및 아세토나이트릴/CO₂기-액 상평형

임교빈,유종훈 수원대학교 산업기술연구소 2004 산업기술연구소논문집 Vol.19 No.-

The phase behavior of Methanol/CO₂ systems was investigated previously by a number of researchers. However, the entire composition range at moderate temperatures was not mapped in a single study Furthermore, extensive acetonitrile/CO₂ vapor-liquid phase information has not been reported. The goals of this research were twofold: (1) to demonstrate the accuracy and precision of visual observation for vapor-liquid phase boundary determination using a high-pressure, variable-volume view cell with the methanol/CO₂ system relative to the data available, and (2) to examine phase behaviors of methanol/CO₂ and acetonitrile/CO₂, commonly used binary fluids for supercritical fluid chromatography and extraction, from 0~1.00 mole fraction CO₂ and over a 25~100℃ temperature range. The results for methanol/CO₂ were found to be very comparable to the literature values.

학회참관기 : 2001 제 3 차 한중 분리기술 학술회의를 다녀와서

임교빈 한국화학공학회 2001 NICE Vol.19 No.6

초임계 Gas Anti-Solvent법을 이용한 재결정에 관한 연구

任敎彬 수원대학교 산업기술연구소 1998 산업기술연구소논문집 Vol.13 No.-

To recrystallize NTO using supercritical Gas Anti-Solvent method we have to find the solvent which has good solvent power for NTO and high expancivity property with the given supercritical fluid simultaneously. DMF, DMSO and other organic solvents were tested for the properties above mentioned. It has been found that DMF has showed high solvent power about 40wt% at 10∼70℃, and 500 v/v% expansivity at the given pressures of 55∼100bar for the range of temperture of 25∼55℃. This result meant that DMF is good solvent for supercritical Gas Anti-Solvent recrystallization of NTO. We have found that the size and shape of particles of recrystallized NTO could be controlled by varying temperature, pressure and concentration of NTO. Fine NTO particles of 20∼30㎛ were obtained in ranges temperatures of 25∼50℃ and pressures of 100∼230.4bar.

초임계 CO₂내에서의 알킬글루코시드의 효소 합성

任敎彬 수원대학교 산업기술연구소 1996 산업기술연구소논문집 Vol.11 No.-

Hexyl-glucoside synthesis has been performed by β-glucosidase from Almonds(E.C.3.2.1.21) in supercritical CO₂which was used as reation medium. The enzyme maintained 80%-86% of its original activity after 72 hours at 15 MPa and 30-50℃. Glucose forms a complex with phenylboronic acid(PBA) to be dissolved into supercritical CO₂using the hydrophobic character of the phenyl group. The conversion reached 13.8% after 72 hours at 15MPa and 40℃.

이중관 형태의 노즐을 이용한 초임계 유체 재결정법

任敎彬 수원대학교 산업기술연구소 2000 산업기술연구소논문집 Vol.15 No.-

In this work, we recrystallize NTO using supercritical CO2 as an anti-solvent. We examine relations between morphology of recrystallized NTO particles and operating conditions for the supercritical recrystallization process which has a annular-type nozzle system. We use methyl alcohol as an organic solvent for NTO, based on its good expansion properties in supercritical CO2. The inside diameter of nozzle is 127㎛. Compressed CO2 flows downward and contacts with sprayed NTO solution drops cocurrently. From these experiments, we can observe the various morphologies of recrystallized NTO for various operating conditions. The typical morphology of recrystallized NTO particles shows agglomerates which are composed of polygon-type or thin plate-type particles. When the flow rate of the CO2 increases and the flow rate of solution decreases, the amount of the plate-shape particles which have thinner thickness increases. From these results, the operating conditions such as temperature, pressure, solution flow rate and nozzle-type are found to be important variables to control the morphology of NTO recrystallized by supercritical fluids

초임계 유체의 흐름방향이 기체-고체계의 물질전달에 미치는 영향

任敎彬 水原大學校 1994 論文集 Vol.12 No.-

Gas-solid mass transfer in CO₂-naphthalene system was studied under subcritical to supercritical conditions. An experimental apparatus of packed bed which contains pelletized naphthalene was originally constructed and the amount of naphthalene dissolved into carbon dioxide is measured at various temperature(35∼55℃), pressure(10∼200atm), and flow rate(0.9∼33.5 STD l/min) of supercritical carbon dioxide. By catalyzing these experimental data, the mass transfer coefficient of naphthalene was modeled with cell model in the literature. The mode of flow of carbon dioxide througth the vertical packed bed can be concerned as the gravity-assisted direction(downward flow) and the gravity-opposed flow and the result is proposed according to the correlation of mass transfer with natural and forced mode of flow. The results are compared with the case of gravity-opposed flow reported in the literature and accordingly we found that the assisted flow can enhance the mass transfer rate about 6∼15% over the case of opposed flow. We, also, found that the effect of natural convection is dominantly important in the vicinity of critical region of carbon dioxide.

환경기술상 청정기술부문 추천기술

임교빈 한국청정기술학회 1996 청정기술 Vol.2 No.1

초임계 이산화탄소를 이용한 웨이퍼 세정

임교빈,유종훈 수원대학교 산업기술연구소 2003 산업기술연구소논문집 Vol.18 No.-

Organic and aqueous solvents are largely used in cleaning processes for semiconductor manufacturing. In this study, we examined a non-plasma, environmentally benign stripping method using supercritical carbon dioxide (SCCO₂) to remove ion implanted photoresist and residues from a wafer surface at temperatures ranging from 80 to 200℃ and at pressures from 150 to 400 bar. Polar cosolvents were added to nonpolar SCCO₂ to improve the stripping efficiency of photoresist and residues. A suggested cleaning mechanism is swelling and plasticization of the polymer by SCCO₂ associated with degradation by the cosolvents, thereby lowering molecular weight and increasing solubility. The I-line photoresist whose chemical structures had been changed after ion implantation was not easily removed by using SCCO₂ containing single cosolvent. However, SCCO₂ containing multiple cosolvents showed a high stripping efficiency of carbonized photoresist (about 90%) under the operating conditions of 80~100℃ and 150~250 bar. The experimental results obtained in this study verified that the SCCO₂ cleaning method is a promising alternative to traditional photoresist wet-stripping techniques.

초임계 이산화탄소를 이용한 감초 내의 글라브리딘 추출

임교빈,유종훈 수원대학교 산업기술연구소 2003 산업기술연구소논문집 Vol.18 No.-

The purpose of this work was to evaluate the feasibility of supercritical carbon dioxide (SCCO₂) extraction of glabridin from various active components in Glycyrrhiza glabra. The extraction experiments were carried out at temperatures ranging from 40 to 80℃ and at pressures from 150 to 420 bar. The effects of process variables such as the type and amount of cosolvents, temperature, and pressure on the extraction yield, chemical composition of the extract, and extraction kinetics were investigated in detail. The chemical compositions of the extract were analyzed by high-performance liquid chromatography. Almost no glabridin was extracted at all extraction conditions when only pure supercritical carbon dioxide was employed as an extraction solvent, whereas a significant amount or glabridin was extracted in the presence of cosolvents such as methanol and ethanol. The experimental results obtained in this study revealed that the extraction yield not only increases but the extraction time also decreases as the concentration of cosolvents in SCCO₂ increases up to about 25%. Methanol was round to be more effective in SCCO₂ extraction of glabridin, leading to 16% improvement in the extraction yield, compared with ethanol.

The Effect of Mixing on the Mass Transfer Enhancement Under Supercritical Conditions

任敎彬 수원대학교 산업기술연구소 1997 산업기술연구소논문집 Vol.12 No.-

나프탈렌-CO₂계에서 임계점 부근의 물질전달 강화에 영향을 미치는 주요 변수를 규명하였다. 본 연구에서 온도는 25∼55℃, 압력은 0∼300 bar 범위 내에서 modified Peng-Robinson EOS를 이용하여 수행되었으며 전체적인 물질전달 강화는 Grashof수에 의하여 예측 가능하였다. Grashof수는 평형상태인 고체 표면과 bulk 상의 초임계유체 사이의 밀도차이에 크게 영향을 받으며 특히 이러한 혼합물의 밀도에 미치는 몰분율의 효과는 infinite dilution partial molar volume(??)이 매우 큰 negative값을 가지는 임계점 부근에서 극대화되어 자연대류에 의한 물질전달이 크게 강화되었으며, 이러한 현상은 임계점 부근의 넓은 온도와 압력에서 나타났다. 그러나 예외적으로 확산 계수가 극히 작은 LCEP부근에서는 Grashof수가 크더라도 자연대류에 의한 물질전달 강화 효과는 감소하였다.