• Bulletin of the Korean Chemical Society
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• 제19권12호
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• pp.1342-1346
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• 1998

The dehydrogenation of ethylbenzene with carbon dioxide has been carried out over ZSM-5 zeolite-supported iron oxide catalyst as well as commercial catalyst (K-Fe2O3) and unsupported iron oxide (Fe3O4) for comparison. In the dehydrogenation over the ZSM-5 zeolite-supported iron oxide catalyst, ethylbenzene is predominantly converted to styrene by an oxidative pathway in the presence of excess carbon dioxide. Carbon dioxide in this reaction is found to play a role as an oxidant for promoting catalytic activity as well as coke resistance of catalyst. On the other hand, both of commercial catalyst and unsupported Fe2O4 exhibit considerable decrease in catalytic activity under the same condition. It is suggested that an active phase for the dehydrogenation with carbon dioxide over ZSM-5 zeolite-supported iron oxide catalyst would be rather a reduced and isolated magnetite (Fe3O4)-like phase having oxygen deficiency in the zeolite matrix.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.303-309
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• 2009

폐 농업용 비닐을 이용한 연료유 생산 공정을 위한 저밀도폴리에틸렌(LDPE)과 에틸렌비닐아세테이트(EVA) 수지에 대한 열분해 반응 실험을 하였다. 질소 분위기에서 상온에서 $650^{\circ}C$까지의 비등온 조건에서의 열분석기(열중량분석기, 시차주사열량계)와 $420^{\circ}C$의 배치형 반응기에서 무촉매 반응과 천연제올라이트, FCC 촉매, 폐 FCC 촉매, 중국 촉매(촉매 A) 등의 제올라이트계 촉매를 사용한 열분해가 행하여졌다. TGA 실험에서 무적제가 첨가된 EVA 수지는 열분해 개시 온도가 $250^{\circ}C$ 근처로 매우 낮아졌으나, 황토와 장수제 첨가는 열분해를 다소 지연시켰다. LDPE에서 제올라이트 계열 촉매는 촉매 A>폐 FCC 촉매>천연제올라이트>LDPE의 순으로 열분해 반응속도를 높이는데 유효하였다. EVA에서 제올라이트 계열 촉매 첨가 시는 폐 FCC 촉매>천연제올라이트>촉매 A>EVA 수지의 순으로 열분해 반응을 촉진시켰다. DSC 실험에서 제올라이트 계열 촉매 첨가 시 촉매 A>폐 FCC 촉매>천연제올라이트>LDPE의 순으로 융해개시 온도와 열분해열이 낮아졌다. 회분식 실험에서 천연제올라이트 첨가 시 시료 중 가장 높은 액상의 연료유 생성수율을 얻었다.

• 청정기술
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• 제19권3호
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• pp.287-294
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• 2013

구리-제올라이트 촉매와 Fe-제올라이트 촉매로 과잉산소 분위기에서 일산화질소의 암모니아 선택적 촉매환원반응을 체계적으로 조사하였다. 촉매는 디젤엔진에서의 SCR기술의 적용을 위하여 구리와 철을 $NH_4$-BEA와 $NH_4$-ZSM-5 제올라이트에 이온교환법과 함침법으로 담지시켜 제조하였다. 촉매의 특성은 BET, XRD, FE-TEM과 SEM/EDS를 사용하여 조사하였다. 고정된 반응조건에서 선택적 촉매환원반응의 활성을 조사한 결과에서 구리를 BEA 제올라이트에 이온교환시켜 제조한 촉매가 $200{\sim}250^{\circ}C$의 저온영역에서 탁월한 성능을 나타내었다. $250^{\circ}C$ 이하의 저온에서 구리-제올라이트 촉매가 Fe-제올라이트 촉매보다 높은 반응활성을 나타내었다. BEA 제올라이트에 담지된 촉매가 ZSM-5 제올라이트에 담지된 촉매보다 $250^{\circ}C$ 이하의 저온에서 우수한 반응활성을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2367-2374
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• 2013

Lysine (Lys) immobilized on zeolite 4A was prepared by a simple adsorption method. The physical and chemical properties of Lys/zeolite 4A were investigated by X-ray diffraction (XRD), FT-IR, Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis. The obtained organic-inorganic composite was effectively employed as a heterogeneous basic catalyst for synthesis of ${\alpha},{\beta}$-unsaturated carbonyl compounds. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present catalyst.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.873-875
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• 2009

Middle distillate was produced by the hydrocracking of F-T wax on the zeolite catalysts. Novel metal loaded zeolite catalysts had good performance for hydrocracking of F-T wax. 2 wt.% Platinum loaded H-Y zeolite catalyst showed the highest selectivity of middle distillate and conversion of F-T wax. H-Y zeolite had more strong acidity site and large pore than that of another zeolite catalyst. So, H-Y zeolilte catalyst showed the best activity for hydrocracking of F-T wax.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.525-530
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• 2014

Titanium dioxide nanotube supported ZSM-5 zeolite composite catalyst was fabricated by decorating ZSM-5 zeolite on the hydrothermally synthesized titanium dioxide via hydrothermal process and subsequent annealing. The catalyst was characterized by X-ray powder diffraction (XRD), Transmission electron microscopy (TEM) and Nitrogen adsorption-desorption (BET). The surface acidity of the catalyst was measured by means of Fourier transform infrared (FT-IR) spectrum of pyridine adsorption. And the catalytic activity for ethanol dehydration to ethylene was evaluated in a continuous flow fixed-bed reactor. Attributed to the increase of the effective surface acid sites caused by titanium dioxide nanotube as electron acceptor, titanium dioxide nanotube supported ZSM-5 zeolite composite catalyst exhibits strongly enhanced activity for ethanol dehydration to ethylene.

• 공업화학
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• 제22권3호
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• pp.323-327
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• 2011

원통형으로 성형된 zeolite sheet (제올라이트를 함유하는 세라믹 종이)는 VOC 제거를 위한 효과적인 흡착로터로서 사용될 수 있다. 본 연구에서는 ZSM-5가 함유된 zeolite sheet 지지체에 Pt를 담지한 후 톨루엔 연소 촉매 성능을 ${\gamma}-Al_2O_3$ 및 cordierite honeycomb 지지체에 담지된 Pt 촉매와 비교하였다. Pt/zeolite sheet 촉매는 $Pt/{\gamma}-Al_2O_3$ 또는 Pt/cordierite honeycomb 촉매에 비하여 톨루엔 연소반응에 높은 활성을 나타냈다. 한편, Pt/zeolite sheet 촉매를 상온에서 $NH_3-H_2O$ 증기로 전처리하면 zeolite sheet에 담지된 Pt 입자의 분산도가 향상되었으며, 톨루엔 연소 촉매 활성이 크게 증가하였다.

• 한국수소및신에너지학회논문집
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• 제14권1호
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• pp.69-80
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• 2003

Nickel catalyst has been used for natural gas reforming with carbon dioxide, In this study, catalyst support used was HY zeolite. The optimum loading of Ni in the catalysts was 13 wt%. The effect of promoters, such as Mg, Mn, and K, was also studied. The addition of promoters to Ni catalyst improved the stability of catalysts and carbon deposition on Ni catalyst was suppressed. The reforming reactivity of promoter-added Ni catalyst was higher than that of Ni catalyst without any promoters. SEM, XRD, BET, TGA and FTIR tests were tried to characterize the catalyst structure before and after reaction.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1301-1304
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• 2010

The Indium modified mesoporous zeolite AlMCM-41 were synthesized by hydrothermal method and characterized by powder X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) techniques. The Knoevenagel condensation of aldehyde with malononitrile or ethyl cyanoacetate was carried out at reflux condition in ethanol by using heterogeneous In/AlMCM-41 catalyst. This method is fast, efficient, easy work-up and eco-friendly to afford the corresponding Knoevenagel adducts. The catalyst was recovered and reused for several cycles with consistent activity.

• 동력기계공학회지
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• 제18권3호
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• pp.14-19
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• 2014

The purpose of the study is to investigate the effect of additive catalyst according to the thermal aging of vanadia SCR catalysts. At a fresh condition, the $3V_2O_5-5WO_5-92TiO_2$ SCR showed the highest NOx conversion rate of about 30%, the performance of 5 kinds of SCR to which additive catalysts were added was not improved due to the insignificant effect of acid site control. For catalysts aged for 12h at $700^{\circ}C$, the SCR to which 3wt% Zeolite was added decreased in NOx conversion rate by 2.5% on average compared to the fresh SCR, it showed higher thermal durability than other additive catalyst. For 3Zeolite with high performance of NOx conversion rate during thermal aging, the Zeolite with stronger durability at a high temperature than other 5 kinds of SCR catalysts decreased the sintering of catalysts.