• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.134-134
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• 2003

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2002년도 추계총회 및 연구발표회 초록집
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• pp.138.1-138
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• 2002

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.166.2-166
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• 2003

• Korean Chemical Engineering Research
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• 제46권1호
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• pp.142-146
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• 2008

Titanium silicalite-1 촉매를 $175^{\circ}C$에서 2일간 $SiO_2-TiO_2$ xerogel을 전구체로 사용하여 수열 합성하였고, 이를 이용하여 allylchloride(ALC) 에폭시화 반응의 속도론 인자를 도출하기 위해 반응온도 $25{\sim}55^{\circ}C$, ALC의 농도 0.2~3.0 M, 과산화수소의 농도 0.2~1.5 M 영역에서 촉매 반응실험을 수행하였다. 초기농도법을 이용하여 반응속도를 구한 후, power rate law, Eley-Rideal, 및 Langmuir-Hinshelwood 모델에 적용한 결과, 큰 차이는 없으나 power rate law에서 실험치와 예측치가 가장 우수하게 일치하였고, 이때 활성화 에너지는 29.7 kJ/mol, 과산화수소에 대한 반응차수는 0.41, ALC에 대한 반응차수는 0.52였다.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.634-638
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• 2004

Titanium silicalite-1 (TS-1) molecular sieve was produced by microwave heating of amorphous titanium-containing solid precursors after impregnation with aqueous TPAOH solution. $SiO_2-TiO_2$ xerogel, sub-micron sized $SiO_2-TiO_2$ prepared by thermal plasma process, and Ti-containing mesoporous silica, Ti-HMS, were tested as the solid phase substrates. Highly crystalline product was obtained within 30 min. after microwave irradiation with yields over 90% using $SiO_2-TiO_2$ xerogel, which showed essentially identical physicochemical properties to TS-1 prepared by conventional hydrothermal method. Excellent catalytic activity was also obtained for 1-hexene epoxidation using $H_2O_2.\;SiO_2-TiO_2$ particles prepared by thermal plasma and Ti-HMS were found inferior as a substrate for TS-1, probably due to difficulties in wetting the surface uniformly with TPAOH.

• 한국포장학회지
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• 제11권1호
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• pp.53-58
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• 2005

Titanoalumino silicalite (TAS) was prepared hydrothermally, and the effects of synthesis parameters such as silica/alumina sources, $SiO_2/TiO_2$ ratio, and aging treatment were investigated. The structure, crystal size, and shape were examined by XRD and SEM, and the extent of titanium incorporation into the zeolite framework was examined using UV-vis DRS spectroscopy. For TAS preparation, aging of ca. 24h was essential, and the faster crystallization rates were achieved with Cab-O-Sil than with Ludox or TEOS as a silica source. In addition, the higher crystallinity and faster crystallization rate were obtained using sodium aluminate as an aluminum source.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.140-142
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• 2002

• 공업화학
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• 제9권5호
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• pp.639-647
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• 1998

알루미늄 함유 티타늄 실리카라이트-1 ([Al]-TS-1) 촉매를 수열합성하고 실리카원, 알루미늄원, $SiO_2/TiO_2$ 몰비, 및 숙성처리와 같은 합성인자들의 영향을 살펴 보았다. 제조한 촉매의 구조, 결정의 크기 및 모양은 X-선 회절분석 및 주사전자 현미경으로 살펴보았으며, UV-vis DRS 분석으로 제올라이트 구조 내로 치환된 티타늄의 상태를 확인하였다. [Al]-TS-1의 합성에 있어서는 약 24시간의 숙성과정이 필수적이었으며, Cab-O-Sil을 실리카원으로 사용한 경우가 Ludox 및 TEOS를 사용한 경우보다 더욱 빠른 결정화 속도를 나타내었다. 알루민산나트륨을 알루미늄원으로 사용한 경우가 질산알루미늄을 사용한 경우보다 더 높은 결정화도를 나타내었고 결정화 시간도 단축되었다. 합성한 촉매의 산화/환원 특성은 과산화수소를 산화제로 2-butanol의 액상 산화를 모델 반응으로 선택하여 검토하였다. 산촉매반응으로 톨루엔 알킬화반응을 수행한 결과, [Al]-TS-1의 산세기는 구조내에 존재하는 티타늄에 기인하여 약해졌으며 para-에틸톨루엔의 선택도는 향상됨을 알 수 있었다.

• 한국재료학회지
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• 제26권3호
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• pp.149-153
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• 2016

Nanosized zeolites were prepared in an autoclave using tetraethoxysilane (TEOS), tetrapropylammonium hydroxide (TPAOH), and $H_2O$, at various hydrothermal synthesis temperatures. Using transmission electron microscopy and particle size analysis, the nanopowder particulate sizes were revealed to be 10-300 nm. X-ray diffraction analysis confirmed that the synthesized nanopowder was silicalite-1 zeolite. Using atomic layer deposition, the fabricated zeolite nanopowder particles were coated with nanoscale $TiO_2$ films. The $TiO_2$ films were prepared at $300^{\circ}C$ by using $Ti[N(CH_3)_2]_4$ and $H_2O$ as precursor and reactant gas, respectively. In the TEM analysis, the growth rate was ${\sim}0.7{\AA}/cycle$. Zeta potential and sedimentation test results indicated that, owing to the electrostatic repulsion between $TiO_2$-coated layers on the surface of the zeolite nanoparticles, the dispersibility of the coated nanoparticles was higher than that of the uncoated nanoparticles. In addition, the effect of the coated nanoparticles on the photodecomposition was studied for the irradiation time of 240 min; the concentration of methylene blue was found to decrease to 48%.