Effect of High Temperature on Swellable Organically Modified Silica (SOMS) and Its Application for Preferential CO Oxidation in H-2 Rich Environment

Basu, Dishari
Ailawar, Saurabh
Çelik, Gökhan
Edmiston, Paul
Ozkan, Umit S.
Transition metal oxide catalysts tend to deactivate in the presence of moisture during hydrogen purification using preferential oxidation (PROX) of carbon monoxide (CO) . Thus, novel water-tolerant catalysts need to be developed. Herein, the evolution of heat treated swellable organically-modified silica (SOMS), a hydrophobic organic-inorganic hybrid material, has been characterized and applied as a catalyst support for PROX under moisture-rich conditions. While the SOMS-supported cobalt manganese oxide was found to be inactive, drastic improvement in CO conversion was observed for heat treated SOMS (HSOMS) supported catalysts. From thermogravimetric analysis and NMR spectroscopy it was found that SOMS retains its structural properties and hydrophobicity up to 400 degrees C. The performance of these catalysts was improved upon using toluene as the impregnation solvent, which enhanced the support wettability and improved active site deposition. The catalyst supported on HSOMS-400 was found to be more water tolerant than a silica-supported catalyst due to Si-O-Si(CH3)(3) groups retained from hexamethyldisilazane (HMDS) derivatization of SOMS.


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Sodium borohydride is stable in alkaline solution, however, it hydrolyses and generates hydrogen gas in the presence of suitable catalyst. By this way hydrogen can be generated safely for the fuel cells. All of the catalyst having been used in the hydrolysis of sodium borohydride, with one exception, are heterogeneous. The limited surface area of the heterogeneous and therefore, have limited activity because of the surface area. Thus, the use of metal nanoclusters as catalyst with large surface area is expe...
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The electrochemical oxidation of several N,N'-polymethylenebis(3,5-di-tert- butylsalicylaldiminato)nickel(II) complexes, Ni(L-x), has been studied by cyclic voltammetry and in situ UV-Vis spectroscopy in DMF Cyclic voltammograms of Ni(L-x) (x = 1-4) complexes displayed two-step oxidation processes under nitrogen gas atmosphere. The first oxidation peak potentials of all the Ni(II) complexes corresponds to the reversible one-electron oxidation process of the metal center, yielding Ni(III) species. EPR spectr...
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Synthesis of ferrocenyl-substituted pyrazoles via the reaction between (2-formyl-1-chlorovinyl)ferrocene and hydrazine derivatives is described. Depending upon the substitution pattern of hydrazine, the reaction affords 1-alkyl/aryl-5-ferrocenylpyrazoles and/or 1-alkyl/ aryl-3-ferrocenylpyrazoles. The reaction appears to be general for a variety of hydrazine derivatives.
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Citation Formats
D. Basu, S. Ailawar, G. Çelik, P. Edmiston, and U. S. Ozkan, “Effect of High Temperature on Swellable Organically Modified Silica (SOMS) and Its Application for Preferential CO Oxidation in H-2 Rich Environment,” CHEMCATCHEM, pp. 3753–3768, 2020, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/70034.