Comprehensive study of surface chemistry of MCM-41 using 29Si CP/MAS NMR, FTIR, pyridine-TPD, and TGA


Autoria(s): Zhao, X. S.; Lu, G.Q.; Whittaker, A.K.; Millar, G.J.; Zhu, H.Y.
Data(s)

1997

Resumo

A comprehensive study was conducted on mesoporous MCM-41. Spectroscopic examinations demonstrated that three types of silanol groups, i.e., single, (SiO)3Si-OH, hydrogen-bonded, (SiO)3Si-OH-OH-Si(SiO)3, and geminal, (SiO)2Si(OH)2, can be observed. The number of silanol groups/nm2, ?OH, as determined by NMR, varies between 2.5 and 3.0 depending on the template-removal methods. All these silanol groups were found to be the active sites for adsorption of pyridine with desorption energies of 91.4 and 52.2 kJ mol-1, respectively. However, only free silanol groups (involving single and geminal silanols) are highly accessible to the silylating agent, chlorotrimethylsilane. Silylation can modify both the physical and chemical properties of MCM-41.

Identificador

http://eprints.qut.edu.au/62044/

Publicador

American Chemical Society

Relação

DOI:10.1021/jp971366+

Zhao, X. S., Lu, G.Q., Whittaker, A.K., Millar, G.J., & Zhu, H.Y. (1997) Comprehensive study of surface chemistry of MCM-41 using 29Si CP/MAS NMR, FTIR, pyridine-TPD, and TGA. Journal of Physical Chemistry B, 101(33), pp. 6525-6531.

Fonte

School of Chemistry, Physics & Mechanical Engineering; Institute for Future Environments; Science & Engineering Faculty

Palavras-Chave #030601 Catalysis and Mechanisms of Reactions #zeolite #MCM-41 #NMR #FTIR #TPD
Tipo

Journal Article