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Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.50A [2011] >
IJC-A Vol.50A(08) [August 2011] >
| Title: | Surface acidic properties of sulphated Fe2O3-TiO2 |
| Authors: | Raj, K Joseph Antony
Prakash, M G
Shanmugam, R
Krishnamurthy, K R
Viswanathan, B |
| Keywords: | Catalysis
Acidity
Density functional calculations
Sulphated iron oxide
Iron oxide
Titania |
| Issue Date: | Aug-2011 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | Mixed iron and titanium oxides with varying
quantities of sulphate species have been prepared by sulphation of ilmenite
followed by calcination. A combined approach involving DFT and DRIFT spectroscopy
has been adopted to determine the appropriate structure for adsorption of
pyridine on sulphated Fe2O3-TiO2 (SFT). The
DRIFT spectra obtained for pyridine adsorbed SFT
samples show equal number of Brønsted and Lewis acid sites. The TG-DTG analysis
reveals the greater affinity for water and hydroxyl groups on SFT. Evaluation
of IR frequencies for various structures based on DFT demonstrates that
the adsorption of water/hydroxyl groups on S and/or Fe leads to the conversion of Lewis acid sites into Brønsted acid sites. Investigation
of Mulliken charges for Fe, Ti, S and N for the pyridine adsorbed SFT
structures demonstrates the preferable adsorption of pyridine on sulphur rather
than on Fe. |
| Page(s): | 1050-1055 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-0975(Online); 0376-4710(Print) |
| Source: | IJC-A Vol.50A(08) [August 2011]
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