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Indian Journal of Chemical Technology (IJCT) >
IJCT Vol.17 [2010] >
IJCT Vol.17(4) [July 2010] >
| Title: | Linde Type-A zeolite synthesis and effect of crystallization on its surface acidity |
| Authors: | Khan, G M Arifuzzaman
Arafat, S M Y
Reza, M N
Razzaque, S M Abdur
Alam, Md. Shamsul |
| Keywords: | LTA zeolite
XRD measurement
FTIR spectroscopy
Surface acidity |
| Issue Date: | Jul-2010 |
| Publisher: | CSIR |
| Abstract: |
An alumino-silicate zeolite, Linde Type-A (LTA) has been prepared from
aluminium powder and sodium metasilicate by hydrothermal process. The zeolite
was characterized by FTIR and X-ray diffraction (XRD) analysis and by measuring
the surface acidity using KOH as adsorbate. The surface acidity of LTA zeolite
varied greatly with varying synthesized conditions such as crystallization
temperature, crystallization time and K+ ion adsorption period. The
Bronsted acid site on the zeolite surface increased with increasing
crystallization temperature and the maximum surface acidity was obtained at 100oC.
Crystal growth
was also dependent on the crystallization time. The surface acidity increased
with increasing crystallization time. The maximum surface acidity due to the
maximum consumption of the K+ ion was observed at 48 h adsorption
time and the value was found to be 0.9 meq/g when Si:Al was 50:50. It was seen
that the surface acidity was more pronounced when ammonium hydroxide solution
as adsorbate and agitated crystallization condition were used. The surface
acidity of the commercial LTA zeolite was compared with the surface acidity of
the synthesized LTA zeolite. It was found that the surface acidity of
synthesized LTA zeolite is slightly greater than commercial LTA zeolite |
| Page(s): | 303-308 |
| ISSN: | 0975-0991 (Online); 0971-457X (Print) |
| Source: | IJCT Vol.17(4) [July 2010]
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