• Title/Summary/Keyword: catalyst preparation

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Polymer Support Immobilized Acidic Ionic Liquid: Preparation and Its Application as Catalyst in the Synthesis of Hantzsch 1,4-Dihydropyridines

  • Jahanbin, Bentolhoda;Davoodnia, Abolghasem;Behmadi, Hossein;Tavakoli-Hoseini, Niloofar
    • Bulletin of the Korean Chemical Society
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    • v.33 no.7
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    • pp.2140-2144
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    • 2012
  • A polymer support immobilized acidic ionic liquid was prepared by copolymerization of 3-vinyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate with styrene in the presence of benzoyl peroxide and its primary application as a solid acidic heterogeneous catalyst to the synthesis of Hantzsch 1,4-dihydropyridines through a one-pot three-component reaction of aromatic aldehydes, ethyl acetoacetate and ammonium acetate was investigated. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and a considerable catalytic activity still could be achieved after third run.

Enhancement of Catalytic Activity of Pt/Alumina by a Novel Pretreatment Method for the CO Oxidation for Fuel Cell Applications (연료전지용 CO의 산화를 위한 백금/알루미나 촉매의 성능향상에 관한 연구)

  • Jo, Myung-Chan
    • Journal of Environmental Science International
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    • v.17 no.12
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    • pp.1307-1314
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    • 2008
  • Hydrogen gas is used as a fuel for the proton exchange membrane fuel cell (PEMFC). Trace amount of carbon monoxide present in the reformate $H_2$ gas can poison the anode of the PEMFC. Therefore, preferential oxidation (PROX) of CO is essential for reducing the concentration of CO from a hydrogen-rich reformate gas. In this study, conventional Pt/$Al_2O_3$ catalyst was prepared for the preferential oxidation of CO. The effects of catalyst preparation method, additive, and hydrogen on the performances of PROX reaction of CO were investigated. Water treatment and addition of Ce enhanced catalytic activity of the Pt/$Al_2O_3$ catalyst at low temperature below $100^{\circ}C$.

Effect of FeNi30 Powder Catalyst by Water Atomizing on Synthesis High-grade Diamond

  • Cheng, Dong-kai;Ma, Hong-qiu;Cao, Dan;Ding, Fu-chang
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.449-450
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    • 2006
  • This paper described the preparation method for composing high-grade synthetic diamond by water atomizing using FeNi30 powder catalyst. The objective of this article is about powder making process using super high water atomizing in the atmosphere of inert gas, and then corroded the powder with a corrosion inhibitor. Finally, FeNi30 catalyst powder with lower oxygen content and good sphericity is produced. The experiment of making diamonds by using cubic press and the performance of the diamonds are also discussed.

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Simple Method of Preparation and Characterization of New Antifungal Active Biginelli Type Heterocyclic Compounds

  • Pothiraj, C.;Velan, A. Senthilkumara;Joseph, J.;Raman, N.
    • Mycobiology
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    • v.36 no.1
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    • pp.66-69
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    • 2008
  • A simple, efficient and cost effective method is described for the synthesis of Biginelli type heterocyclic compounds of dihydropyrimidinones analogous. They were prepared from a reaction mixture consisting of substituted benzaldehydes, thiourea and ethylacetoacetate using ammonium dihydrogenphosphate as catalyst. The procedure for the preparation of the compounds is environmentally benign and safe which is advantageous in terms of experimentation, catalyst reusability, yields of the products, shorter reaction times and preclusion of toxic solvents. The four new synthesised compounds were tested for their antifungal activity. They have good antifungal activity comparing to the standard (Fluconazole).

Preparation, Characterization and First Application of Aerosil Silica Supported Acidic Ionic Liquid as a Reusable Heterogeneous Catalyst for the Synthesis of 2,3-Dihydroquinazolin-4(1H)-ones

  • Yassaghi, Ghazaleh;Davoodnia, Abolghasem;Allameh, Sadegh;Zare-Bidaki, Atefeh;Tavakoli-Hoseini, Niloofar
    • Bulletin of the Korean Chemical Society
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    • v.33 no.8
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    • pp.2724-2730
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    • 2012
  • A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

Fabrication of a solid catalyst using coal fly ash and its utilization for producing biodiesel

  • Go, Young Wook;Yeom, Sung Ho
    • Environmental Engineering Research
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    • v.24 no.2
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    • pp.324-330
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    • 2019
  • To recycle raw fly ash (RFA), a waste from thermal power plants, it was used to prepare solid catalysts which have many advantages compared with homogenous catalysts. When biodiesel was produced from soybean oil using RFA, only 1.2% of biodiesel conversion was obtained. A metal hydroxide, NaOH, KOH or $Ca(OH)_2$, was mixed with the acid-treated fly ash (ATFA), and the mixture was calcined at $700^{\circ}C$ for 3 h to prepare the solid catalyst. The solid catalyst prepared by mixing ATFA with NaOH, designated as SC-Na, showed a better performance than those prepared by mixing ATFA with KOH or $Ca(OH)_2$, respectively. The optimal mass ratio of ATFA with NaOH was 1:3, at which the proportion of $Na_2O$ increased to 60.2% in SC-Na, and 97.8% of biodiesel conversion was achieved under optimal reaction conditions (2 w% SC-Na relative to oil and 5 mL-methanol/g-oil at $50^{\circ}C$ for 4 h). Finally, a batch operation was repeatedly carried out to test the feasibility of reusing the solid catalyst, and more than 96% biodiesel conversion was stably achieved for the third round of operations. This study shows that RFA was successfully recycled to solid catalysts through a simple preparation method, and the solid catalyst was reused for the production of biodiesel with high conversion.