A novel procedure for the synthesis of NH3 incorporated VPO phases
IR@IIP: CSIR-Indian Institute of Petroleum, Dehradun
View Archive Info| Field | Value | |
| Creator |
Datta,Arunabha
Agarwal,Monika Dasgupta,Soumen |
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| Date |
2010-07-20T09:02:50Z
2010-07-20T09:02:50Z 2010-07-20T09:02:50Z |
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| Identifier |
J. Mater. Chem., 2002, 12, 1892–1897
http://hdl.handle.net/123456789/671 |
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| Description |
It has been observed that as a function of a time delay introduced between the onset of the reduction of V2O5
with hydroxylamine hydrochloride and the addition of phosphoric acid, in the aqueous route preparation of the
catalytically important VOHPO4?0.5H2O phase, a series of NH3 incorporated phases are obtained. Up to delay
times of 3 min the crystalline VOHPO4?0.5H2O phase is obtained whereas a weakly crystalline hemihydrate is
formed at a delay time of 4 min. Longer delay times result in X-ray amorphous phases until at delay time of
10 min and above a new crystalline phase containing mixed-valent vanadium emerges. All the phases obtained
with delay times of 4 min and above have NH3 incorporated into them. The weakly crystalline
VOHPO4?0.5H2O phase as well as the X-ray amorphous phases undergo transformation to a crystalline
vanadyl pyrophosphate phase on calcination at 723 K in spite of having NH3 incorporated into them. The
in-situ generation of NH3 during the preparation procedure is a hitherto unreported aspect of VPO chemistry
and provides a convenient method for the preparation of novel NH3 incorporated VPO phases which could
have strong potential as catalysts for alkane oxidation as well as for ammoxidation reactions.
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| Language |
en_US
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| Subject |
NH3
VPO Phases |
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| Title |
A novel procedure for the synthesis of NH3 incorporated VPO phases
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| Type |
Article
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