• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2584-2592
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• 2011

Nickel nanoparticle-poly(N-vinyl-2-pyrrolidone)/$TiO_2-ZrO_2$ composite (Ni-PVP/$TiO_2-ZrO_2$) was prepared by in situ polymerization method. The physical and chemical properties of Ni-PVP/$TiO_2-ZrO_2$ were investigated by XRD, FT-IR, BET, TGA, SEM and TEM techniques. The catalytic performance of this novel heterogeneous catalyst was determined for the Suzuki-Miyaura cross-coupling reaction between aryl halides and phenylboronic acid in the presence of methanol-water mixture as solvent. The effects of reaction temperature, the amount of catalyst, amount of support, solvent, and amount of metal for the synthesis of Ni-PVP/$TiO_2-ZrO_2$, were investigated as well as recyclability of the heterogeneous composite. The catalyst used for this synthetically useful transformation showed considerable level of reusability besides very good activity.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2618-2626
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• 2010

In this paper poly (4-methyl vinylpyridinium hydroxide)/SBA-15 composite was prepared as a highly efficient heterogeneous basic catalyst by in situ polymerization method for the first time. It was characterized by XRD, FT-IR, BET, TGA, SEM and back titration using NaOH. This catalyst exhibited the excellent catalytic activities for the Knoevenagel condensation of various aldehydes with ethyl cyanoacetate. Over this catalyst, ${\alpha},{\beta}$-unsaturated carbonyl compounds were obtained in the reasonable yield at $95^{\circ}C$ in 10 - 30 min in $H_2O$ as a solvent with a 100% selectivity to the condensation products. Catalyst could be easily recycled after the reaction and it could be reused without the significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions and operational simplicity with reusability of the catalyst were the salient features of the present synthetic protocol. Presence of $H_2O$ as a solvent was also recognized as a "green method".

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1445-1453
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• 2013

$Zn_{(1-x)}Ni_xAl_2O_4$ (x = 0.0-1.0) spinels were prepared at $800^{\circ}C$ by co-precipitation method and characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. The specific surface area was determined by BET. SEM image showed nano sized spherical particles. XPS confirmed the valence states of the metals, showing moderate Lewis character for the surface of materials. The powders were successfully used as new heterogeneous catalysts of Biginelli's reaction, a one-pot three-component reaction, leading to some dihydropyrimidinones (DHPMs). These new catalysts that produced good yields of DHPMs, were easily recovered by simple filtration and subsequently reused with persistent activity, and they are non-toxic and environmentally friendly. The optimum amount of catalyst is 20% by weight of benzaldehyde derivatives, while the doping amount has been found optimal for x = 0.1.

• 한국대기환경학회지
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• 제12권4호
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• pp.487-494
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• 1996

Simultaneous effects of $C_2H_4$ injection and heterogeneous chemical reactions on non-thermal plasma process to remove $SO_2$ and NOx from flue gas were investigated in the present experimental study. The present results showed that 40% of the electrical power can be reduced in $C_2H_4$ injection and heterogeneous chemical reaction are simultaneously included in the non-thermal plasma precess. As an effort to apply the non-thermal plasma technique to practical flue gas treatment system, a wire-plate type reactor which has technically similar geometry of industrial electrostatic precipitators is used instead of other types of reactors, such as wire-cylinder, packed-bed and surface discharge which are inappropriate to industrial application. In the present study, the photo pictures of positive streamer corona taken by ICCD camera, voltage and current oscillograms, and design criteria of a wire-plate type reactor are also shown, which are needed for industrial application of the non-thermal plasma process.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.225-228
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• 2011

Poly(4-vinylpyridine)-supported $Br{\phi}nsted$ acids (P4VP-HX) were prepared by wet impregnation technique. These supported acids were found as efficient heterogeneous green catalysts for acetylation of alcohol, amine and phenol with different catalytic activities. The wide application of P4VP-HX as reusable solid acid catalyst in organic reactions is possible because of its simple preparation and handling, stability, simple work up procedure.

• Bulletin of the Korean Chemical Society
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• 제5권2호
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• pp.79-82
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• 1984

This study concerns about catalyic cracking of iso-octane over cation ($Cd^{2+},\;Ca^{2+}\;and\;La^{3+}$) exchange mordenites. It deals with mordenite shape selectivity and with kinetics of this catalytic reaction. The striking feature was that over the region of cracking temperature investigated, 523-665K, the yield of isobutene was predominant, relative to that of larger or smaller carbon chain(s). This permits kinetic analysis of the heterogeneous catalytic system in terms of the modified pulse-version microcatalytic chromatography. The observed activation energy ($E_a,\;KJ\;mol^{-1}$) was found to be 46 for Cd-M, 57 for Ca-M and 59 for La-M, respectively.

• 대한화학회지
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• 제38권9호
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• pp.695-700
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• 1994

여러가지 불균일 촉매$(Rh/Al_2O_3,\;Pd/C,\;Ni,\;Al_2O_3,\;Active\;carbon)$를 이용하여 CFC-113a의 가수소 분해반응을 액상과 기상에서 각각 조사하였다. 액상반응에서는 각 촉매에 따라 반응성은 차이가 났지만, 95% 이상의 높은 선택성으로 $HCFC-123(CF_3CHCl_2)$을 주었다. 특히 $Al_2O-3$가 액상반응에서 상당히 높은 반응성과 선택성을 보인 것은 주목할 만하다. 기상반응의 경우, 전이금속이 포함된 촉매(Pd/C, Pt/C)를 사용하였을 때에는 과수소화물인 $HCFC-133a(CF_3CH_2Cl)$와 HFC-143a(CF_3CH_3)$가 생성되었다. 한편, 액상반응에서 활성을 보이던 $Al_2O_3$는 기상반응에서는 거의 반응성을 보이지 않았다. $Al_2O_3$의 경우 용매로 THF를 사용하였을 경우에는 비교적 부반응 없이 깨끗하게 반응이 진행되었지만, MeOH를 사용하였을 때는 용매로 부터 $CH_3OCH_3$과 $CH_3CH_2OCH_3$ 등이 생성되면서 가수소 분해반응이 진행되었다. 따라서 액상반응에서는 용매의 역할이 중요한 것으로 해석하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.340-343
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• 2006

In this paper, heat and mass transfer characteristics through experimental and numerical study are extensively investigated in steam reform ins reactor under given operating conditions. In order to get simulated data at outlet of the reformer, heterogeneous reactor model is incorporated. As the reaction also takes place in porous media, two medium approach is used to take into account thermally non-equilibrium phenomena between catalyst and bulk gas. In steam reforming reaction, heat transfer issue is so significant that geometrical configuration study is also conducted.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1119-1120
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• 2010

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.146-146
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• 2001