MCM-41 mesoporous molecular sieves supported nickel—physico-chemical properties and catalytic activity in hydrogenation of benzene

2002 ◽  
Vol 188 (1-2) ◽  
pp. 85-95 ◽  
Author(s):  
A Lewandowska ◽  
S Monteverdi ◽  
M Bettahar ◽  
M Ziolek
2001 ◽  
Vol 171 (1-2) ◽  
pp. 229-241 ◽  
Author(s):  
Rodica Tismaneanu ◽  
Biswajit Ray ◽  
Rafael Khalfin ◽  
Rafi Semiat ◽  
Moris S. Eisen

1996 ◽  
Vol 431 ◽  
Author(s):  
Partha P. Paul ◽  
Michael A. Miller ◽  
Martin J. Heimrich ◽  
Stuart T. Schwab

AbstractA lean NOx catalyst is needed to control NOx emissions generated by oxygen-rich combustion processes to obtain higher fuel economy. We have developed such a catalyst using modified mesoporous molecular sieves (MCM-41). An iron(II)-complex impregnated MCM-41 has been synthesized which has been further treated with [Pd(NH3)4]Cl2. This treatment resulted in further exchange of Na+ ions of the molecular sieves with Pd(NH3)42+ thus forming Catalyst A. The catalytic activity towards NOx, CO and HC was studied using simulated exhaust gas, as well as engine exhaust gas.


2011 ◽  
Vol 233-235 ◽  
pp. 234-237 ◽  
Author(s):  
Sa Liu ◽  
Jian Wei Guo ◽  
Chu Fen Yang ◽  
Long Huan Li ◽  
Yi Hua Cui

Al-containing mesoporous molecular sieves(Al-MCM-41) were synthesized at ambient temperature. The structures of samples were characterized by XRD, N2-adsorption/desorption isotherms and FT-IR, etc. The evaluation results showed that Al-MCM-41 had higher catalytic activity for isomerization conversion of endo-tetrahydrodicyclo-pentadiene (endo-TCD) into exo-tetrahydrodicyclo-pentadiene (exo-TCD) and adamantane (AdH). Loading inorganic acid on the surface of Al-MCM-41 led increase of its catalytic activity and the yield of adamantane.


1994 ◽  
Vol 371 ◽  
Author(s):  
A. Sayari ◽  
V.R. Karra ◽  
J.S. Reddy ◽  
I.L. Moudrakovski

AbstractA series of crystalline mesoporous molecular sieves were prepared using alkyl hexadecyl dimethyl ammonium bromide salts (C16H33)(CnH2n + 1)(CH3)2NBr, in which the number of carbon atoms (n) in one alkyl group was varied from 1 to 12. The influence of (n) value on the nature of the final phase obtained and on its pore size was investigated. A hexagonal phase was obtained for n = 1, 3, 5 and 7, while a lamellar phase was obtained for all other templates. Vanadium and titanium modified MCM-41 molecular sieves were also prepared in the presence of C12H25(CH3)3N+ and C16H33(CH3)3N+ ions, respectively. These materials were characterized by XRD, nitrogen physisorption, FTIR, solid state NMR, XPS, UV-Vis and catalytic testing in the oxidation of 1-naphthol, 2,6-di-tert-butylphenol, norbornylene, n-hexane and propylamine. Ti-MCM-41 exhibited considerable catalytic activity only in the oxidation of aromatics, olefins and alcohols. V-MCM-41 was found to be a good catalyst in the oxidation of aromatics and alkanes.


2016 ◽  
Vol 9 (2) ◽  
pp. 171-178 ◽  
Author(s):  
Ulka Suryavanshi ◽  
Arun V. Baskar ◽  
Veerappan V. Balasubramanian ◽  
Salem S. Al-Deyab ◽  
Abdullah Al-Enizi ◽  
...  

2003 ◽  
Vol 68 (10) ◽  
pp. 1861-1876 ◽  
Author(s):  
Hynek Balcar ◽  
Jan Sedláček ◽  
Jan Svoboda ◽  
Naděžda Žilková ◽  
Jiří Rathouský ◽  
...  

Hybrid catalysts for polymerization of acetylenes were prepared by anchoring, via (3-aminopropyl)trimethoxysilane linker, the [Rh(cod)Cl]2 complex on siliceous mesoporous molecular sieves differing in the pore size and architecture (MCM-41, MCM-48 and SBA-15). In comparison with [Rh(cod)Cl]2 used as homogeneous catalyst, all hybrid catalysts exhibited comparable or even higher catalytic activity in the polymerization of phenylacetylene and 4-ethynyl-N-{4-[(trimethylsilyl)ethynyl]benzylidene}aniline. The initial polymerization rate increased with increasing accessibility of mesoporous surface of catalysts in the order: MCM-41 < MCM-48 < SBA-15. Molecular weights of the prepared polymers increased in reverse order suggesting suppression of the chain growth termination reactions by space limitations in the pores. No effect of catalyst support on the microstructure of formed polymers was found.


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