Emulsion 을 이용한 미세 ZnO 의 제조

주창식,구준표 ( Chang Sik Ju,Jun Pyo Ku ) 한국공업화학회 1997 응용화학 Vol.1 No.1

W/O micro-emulsions were made of zinc nitrate aqueous solution with HMTA and kerosine in the presence of Span #80, and zinc oxide was precipitated in W/O micro-emulsions. The shape, size and particle size distribution of zinc oxide produced were measured by SEM and Particle Size Analyzer. The effects of process parameters on the physical properties of zinc oxide were experimentally examined. Spherical fine zinc oxide particle with the average diameter of 0.1 - 1 ㎛ were obtained in W/O micro-emulsions, even if the initial zinc concentration of precipitating solutions and conversion were high.

에멀젼을 이용한 단분산 미세 산화아연 입자의 제조 및 특성

주창식,구준표 ( Chang Sik Ju,Jun Pyo Ku ) 한국공업화학회 1998 공업화학 Vol.9 No.6

TTA와 TOPO를 이용한 수용액 중의 리튬이온 용매추출

주창식 ( Chang Sik Ju ),이전규 ( Jeon Kyu Lee ),정상구 ( Sang Gu Jeong ),구수진 ( Su Jin Koo ),김시영SiYoungKim 한국화학공학회 2013 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.51 No.1

For the purpose of development of the extraction process of lithium ion from concentrated water eliminated from desalination process, an experimental research on the solvent extraction of lithium ion from aqueous solutions was performed. The effects of operating parameters, such as concentration of extractant, ratio of extracting solution/aqueous solution, pH of aqueous solution, were examined. The effect of sodium chloride, the major component of sea water, was also examined. Lithium ion in aqueous solutions of pH=10.2~10.6 adjusted by ammonia solution was most effectively extracted by extracting solution composed of 0.02 M TTA and 0.04 M TOPO in kerosine. The addition of sodium chloride in lithium aqueous solution significantly interfered the extraction of lithium ion.

RESS 공정에 의한 griseofulvin 미세입자의 제조

주창식(Chang Sik Ju),천재기(Jae Kee Cheon),이석희(Seok Hee Lee),홍성수(Seong Soo Hong),김홍룡(Hong Lyong Kim),우기주(Ki Ju Woo) 한국공업화학회 2002 공업화학 Vol.13 No.1

초임계 유체를 이용하여 의약품 입자의 크기와 형상을 제어하는 기술 개발 연구의 일환으로, RESS 공정을 사용하여 griseofulvin의 미세입자를 제조하는 실험을 행하였다. 초임계 유체는 CO_2를 사용하였고, 팽창관으로는 orifice disk와 capillary nozzle을 사용하였다. 침출온도와 침출압력 등 통상적으로 중요시되는 조작변수들은 물론, 팽창관의 종류와 형태, 특히 결정화 매체의 종류 및 결정화조 내부로 유입되는 질소 기류가 생성되는 griseofulvin 미세 입자의 크기와 형상에 미치는 영향을 실험적으로 조사하였다. 결정화 매체로 수용액을 사용하면 대기를 사용한 경우보다 생성되는 입자의 크기와 결정성이 증가하였으며, 1 vol%의 Tween 80 수용액을 사용한 경우에 입자간의 응집이 최소가 되는 것을 알았다. 팽창관 주위로 고온의 질소 기류를 유입시키면 매우 미세한 입자를 얻을 수 있었다. For the purpose of development of a supercritical process, controlling the shape and size of the pharmaceutical products, we performed experiments on the RESS process preparing griseofulvin fine particles. Supercritical fluid was CO_2, and orifice disk and capillary nozzle were adapted as expansion devices. Besides leaching temperature and pressure, which are rhe major operating parameters for the common researches in RESS process, we examined the effect of crystallization media and introduction of hot N_2 stream to the crystallization unit on the shape and size of griseofulvin fine particles. When supercritical griseofulvin solutions were expanded into aqueous solutions, size and crystallinity of the particles increased compared to those expanded into atmosphere. Our results showed that very fine griseofulvin particle could be obtained by introducing hot N_2 stream to the atmospheric crystallization unit.

수열합성법에 의한 TiO2 분말 제조와 광촉매 특성

주창식 ( Chang Sik Ju ),정상구 ( Sang Gu Jeong ),나석은 ( Seok En Na ),김시영 ( Si Young Kim ),김석현 ( Scok Hyeon Kim ) 한국화학공학회 2013 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.51 No.2

TiO2 powders were prepared from titanium (IV) sulfate (Ti(SO4)2) solution using ammonia solution at low reaction temperature (80~100 oC) and atmospheric pressure by hydrothermal precipitation method without calcination. The effect of reaction conditions, such as reaction temperature, initial concentration of titanium (IV) sulfate (Ti(SO4)2) solution, pH of mixture solution and the physical properties of the prepared TiO2, such as crystallite structure, crystallite size were investigated. The photocatalytic activity of prepared TiO2 was tested by the photolysis of brilliant blue FCF (BB-FCF) under the UV and the analysis of UV-VIS diffuse reflectance spectroscopy (DRS). The physical properties of prepared TiO2 were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence spectrometer (PL), particle size distribution measurements. The crystallite size and crystallinity of prepared TiO2 increased with increasing titanium (IV) sulfate (Ti(SO4)2) concentration, but photocatalytic activity decreased. The crystallite size decreased with increasing pH of mixture solution, but photocatalytic activity increased. The crystallinity and photocatalytic activity increased with increasing reaction temperature. The results showed that anatase type TiO2 could be prepared by hydrothermal precipitation method using titanium (IV) sulfate (Ti(SO4)2) solution and ammonia solution at low reaction temperature and atmospheric pressure without calcinations

목질계 활성탄을 이용한 수중의 2,4-Dinitrophenol 흡착 제거

주창식 ( Chang-sik Ju ),이민규 ( Min-gyu Lee ) 한국환경과학회 2017 한국환경과학회지 Vol.26 No.5

The removal characteristics of 2,4-dinitrophenol (2,4-DNP) from an aqueous solution by commercial Wood-based Activated Carbon (WAC) have been studied. The effects of various experimental parameters were investigated using a batch adsorption technique. The adsorption capacity of 2,4-DNP by WAC increased with a decrease in the dosage and particle size of WAC, temperature and the initial pH of the solution, and increased with an increase in the initial concentration of the solution. The adsorption equilibrium data were best described by the Redlich-Peterson isotherm model. The maximum adsorption capacities of 2,4-DNP by WAC were 573.07 mg/g at 293 K, 500.00 mg/g at 313 K, and 476.19 mg/g at 333 K, decreasing with increasing temperature. The kinetic data were well fitted to the pseudo-second-order model, and the results of the intra-particle diffusion model suggested that the adsorption process was mainly controlled by particle diffusion. The thermodynamic analysis indicated that the adsorption of 2,4-DNP by WAC was an endothermic and spontaneous process.

제주 화산석으로부터 합성한 Na-A 제올라이트에 의한 Cu 이온의 흡착 특성

주창식 ( Chang-sik Ju ),이창한 ( Chang-han Lee ),이민규 ( Min-gyu Lee ) 한국환경과학회 2018 한국환경과학회지 Vol.27 No.5

The adsorption characteristics of Cu ions were studied using the zeolite Na-A synthesized from Jeju volcanic rocks. The effects of various operating parameters such as initial concentration of Cu ions, contact time, solution pH, and solution temperature were investigated in batch experiments. The adsorption of Cu ions by Na-A zeolite was fitted well by pseudo-second-order kinetics and the Langmuir isotherm model. The maximum adsorption capacity determined using the Langmuir isotherm model was 152.95 mg/g. In addition, the adsorption of Cu ions by zeolite Na-A was primarily controlled by particle diffusion model in comparison with the film diffusion model. As the temperature increased from 303 K to 323 K, ΔG˚ decreased from -2.22 kJ/mol to -3.41 kJ/mol, indicating that the adsorption of Cu ions by Na-A zeolite is spontaneous process.

마이크로에멀젼에서 제조된 나노크기의 이산화티탄에 의한 p - 니트로페놀의 광분해 반응

이만식(Man Sik Lee),이근대(Gun Dae Lee),주창식(Chang Sik Ju),임권택(Kwon Taek Lim),홍성수(Seong Soo Hong) 한국공업화학회 2002 공업화학 Vol.13 No.3

음이온의 Aot(sodium bis(2-ethylhexyl) sulfosuccinate) 계면활성제를 사용하여 나노크기의 TiO_2를 제조하였으며, TEM, XRD, BET, UV-DRS, TGA-DTA 등을 사용하여 마이크로에멀젼을 이용한 나노입자 제조시 W_0(H_2O/AOT)비, R (H_2O/TTIP)비에 따른 입자의 크기 및 결정성 등 물리성 성질을 조사하였다. 또한 제조된 TiO_2 나노입자의 광촉매적 특성을 알아보기 위해 회분식 반응장치를 이용하여 p-니트로페놀의 광분해반응의 활성을 조사하였다. 제조된 TiO_2 나노입자는 소성온도 300~600 ℃의 범위에서 anatase 구조가 형성되었으며, 소성온도 700 ℃에서 anatase 구조에서 rutile 구조로 전이되기 시작하였다. 입자크기는 W_0비 및 R 비가 증가함에 따라 증가하였으나, W_0 비가 더 큰 영향을 나타내었다. 한편 p-니트로페놀의 광분해반응에서 반응성은 표면적과 결정크기보다는 입자 결정성의 영향을 많이 받았다. 또한 500 ℃에서 소성된 TiO_2 촉매가 순수한 anatase 구조를 가지며 가장 높은 p-니트로페놀 분해활성을 보여주었다. Nanosized titania sol has been produced by the controlled hydrolysis of titanium tetraisopropoxide(TTIP) in sodium bis(2-ethylhexyl) sulfosuccinate(AOT) reverse micelles. The physical properties, such as crystallite size and crystallite size and crystallinity according to R and W. ratios have been investigated by TEM, XRD, BET, UV-DRS, TGA and DTA. In addition, the photocatalytic degradation of p-nitrophenol has been studied in a batch reactor in the presence of UV light to compare the photocatalytic activity of prepared nanosized titania. It has shown that the anatase structure appeared in the 300~600 ˚C calcination temperature range, and the conversion of anatase into rutile started above 700 ˚C. The crystallite size increased with increased R and W. ratios, but W. ratio showed a stronger effect on the crystallite size than R ratio. In the photocatalytic degradation of p-nitrophenol, the photocatalytic activity was mainly determined by the crystallinity of titania. In addition, the titania calcined at 500 ˚C resulted in the pure anatase structure that had the highest activity of the photocatalytic degradation of p-nitrophenol.

실리카 담지 12-몰리브도인산 촉매상에서의 아산화질소에 의한 메탄의 부분산화반응

홍성수,우희철,주창식,이근대,( Seong Soo Hong,Hee Chul Woo,Chang Sik Ju,Gun Dae Lee,J . B . Moffat ) 한국공업화학회 1994 공업화학 Vol.5 No.1

실리카에 담지된 혜테로폴리산 촉매에서 아산화질소에 의한 메탄의 부분산화반응을 연구하였다. 여러 가지의 반응조건, 즉 반응온도, 반응물의 분압, 접촉시간, 촉매의 담지량 및 전처리온도 등이 전환율이나 생성물의 선택도 및 속도론에 미치는 영향이 연구되었다. 20wt%로 담지된 촉매가 전환율과 포름알데히드의 수율에 있어서 가장 높은 값을 보여 주었다. 메탄의 전환반응에서의 속도식을 구한 결과, 메탄에 대해서는 1차식을 보여 주었고, 아산화질소에 대한 반응차수는 약 0.4였다. 또한 전체반응의 겉보기 활성화에너지는 30.78 ㎉/mole 이었다. 반응물 중에 첨가된 소량의 사염화탄소는 메탄의 산화반응에서 실리카 담지 HPMo촉매의 활성을 증가시키는 반면에, 반응물에 첨가된 물은 오히려 활성을 감소시키는 것을 볼 수 있었다. The partial oxidation of methane with nitrous oxide on silica-supported metal-oxygen cluster compounds, known as heteropoly acids, has been studied. The effects of several variables such as reaction temperature, partial pressure of reactants, residence time, loading of the catalysts, and pretreatment temperature, on the conversion and product distribution were observed. The kinetics also has been studied. The conversion and yield of formaldehyde show maximum values at a loading of 20 wt%. The apparent reaction order of methane conversion is ca. 1.0 with respect to CH_4 and ca. 0.4 with respect to N_2O. In addition, the apparent activation energy is 30.78 ㎉/mole. The addition of small quantities of tetrachloromethane to the reactant stream enhanced the activity of the silica-supported HPMo in the oxidation of methane, whereas water introduced to the reactant decreased the activity of catalyst under present study.

라텍스 개질 콘크리트용 Carboxylated Styrene Butadiene 라텍스의 제조와 적용 특성

이봉규 ( Bong Kyu Lee ),주창식 ( Chang Sik Ju ) 한국화학공학회 2012 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.50 No.6

라텍스 개질 콘크리트의 혼화용 라텍스를 개발할 목적으로 carboxylated styrene butadiene 라텍스를 이단계 유화중 합법으로 제조하고 콘크리트에 적용하는 실험을 수행하였다. 음이온 유화제로는 sodium dodecylbenzene sulfonate와 sodium salt of lauryl sulfate를 선정하였고, 라텍스 안정제로는 nonylphenoxy poly(ethyleneoxy) ethanol 계열의 동족체 들(n=10, 20, 40)을, 그리고 potassium persulfate와 sodium bisulfite를 redox 개시제로, Na2HPO4와 K2CO3를 전해질로 각각 사용하였다. 중합안정성에 대한 음이온 유화제의 종류와 사용량의 영향 및 입자크기의 전해질 농도 의존성을 실 험적으로 고찰하여 LMC용 라텍스 제조에 적합한 중합처방을 제시하였다. 이 중합처방으로 제조한 라텍스의 LMC 용 도에 대한 적용성을 시험한 결과, 슬럼프와 공기량은 한국도로공사의 품질기준을 충족하며, 역학적 물성시험 결과에서 는 28일간 경화시킨 시편의 압축강도와 휨강도가 품질기준보다 각각 39.6, 87.3% 더 높은 증진효과가 발현됨을 확인 하였다. For the purpose of development of the latex suitable for latex modified concrete, experimental researches on the preparation of carboxylated styrene butadiene latex by the method of the two-step emulsion polymerization and application to concrete were performed. Sodium dodecylbenzene sulfonate and sodium salt of lauryl sulfonate were selected as anionic emulsifiers, and nonylphenoxy poly (ethyleneoxy) ethanols (n=10, 20, 40) as latex stabilizer. Potassium persulfate and sodium bisulfite were used as redox initiator, besides Na2HPO4 and K2CO3 as electrolytes. Polymerization recipe of latex suitable for latex modified concrete were suggested from the experimental researches on the effects of anionic emulsifiers and their concentration on the polymerization stability, and the effect of electrolytes concentration on the particle size of latex. Physical properties, such as slump, air contents, compressive and flexural strength, of latex prepared by suggested polymerization recipe were examined. The experimental results showed that latex modified concrete satisfied the quality standards in slump and air contents. Furthermore, it was turned out that the compressive and the flexural strength of latex modified concrete with 28 days curing time showed appreciably improvements.