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Title: Dehydrogenation kinetics of as-received and ball-milled LiAlH{sub 4}

Abstract

In this paper, we investigate the dehydrogenation kinetics of LiAlH{sub 4} into Li{sub 3}AlH{sub 6} (reaction I) and further into LiH (reaction II). We find the apparent activation energies to be {approx}80 and 100kJ/mol for reactions I and II, respectively. Furthermore, we investigate the effect of ball milling on crystallite size and the dehydrogenation kinetics of both reactions I and II. We find a clear correlation between crystallite size and dehydrogenation kinetics of reaction I. On the other hand, we find the kinetics of reaction II to be independent of the crystallite size. This indicates that reaction I is limited by a mass transfer process, while reaction II is limited by the intrinsic kinetics.

Authors:
 [1];  [2];  [2]
  1. Materials Research Department, Riso National Laboratory, DK-4000 Roskilde (Denmark) and Interdisciplinary Research Center for Catalysis, Department of Chemical Engineering, Technical University of Denmark, DK-2800 Lyngby (Denmark). E-mail: andr1976@gmail.com
  2. Materials Research Department, Riso National Laboratory, DK-4000 Roskilde (Denmark)
Publication Date:
OSTI Identifier:
20784813
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 178; Journal Issue: 12; Other Information: DOI: 10.1016/j.jssc.2005.09.027; PII: S0022-4596(05)00423-8; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACTIVATION ENERGY; ALUMINIUM HYDRIDES; HYDROGEN STORAGE; KINETICS; LITHIUM HYDRIDES; MASS TRANSFER; X-RAY DIFFRACTION

Citation Formats

Andreasen, A., Vegge, T., and Pedersen, A.S. Dehydrogenation kinetics of as-received and ball-milled LiAlH{sub 4}. United States: N. p., 2005. Web. doi:10.1016/j.jssc.2005.09.027.
Andreasen, A., Vegge, T., & Pedersen, A.S. Dehydrogenation kinetics of as-received and ball-milled LiAlH{sub 4}. United States. doi:10.1016/j.jssc.2005.09.027.
Andreasen, A., Vegge, T., and Pedersen, A.S. Thu . "Dehydrogenation kinetics of as-received and ball-milled LiAlH{sub 4}". United States. doi:10.1016/j.jssc.2005.09.027.
@article{osti_20784813,
title = {Dehydrogenation kinetics of as-received and ball-milled LiAlH{sub 4}},
author = {Andreasen, A. and Vegge, T. and Pedersen, A.S.},
abstractNote = {In this paper, we investigate the dehydrogenation kinetics of LiAlH{sub 4} into Li{sub 3}AlH{sub 6} (reaction I) and further into LiH (reaction II). We find the apparent activation energies to be {approx}80 and 100kJ/mol for reactions I and II, respectively. Furthermore, we investigate the effect of ball milling on crystallite size and the dehydrogenation kinetics of both reactions I and II. We find a clear correlation between crystallite size and dehydrogenation kinetics of reaction I. On the other hand, we find the kinetics of reaction II to be independent of the crystallite size. This indicates that reaction I is limited by a mass transfer process, while reaction II is limited by the intrinsic kinetics.},
doi = {10.1016/j.jssc.2005.09.027},
journal = {Journal of Solid State Chemistry},
number = 12,
volume = 178,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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  • No abstract prepared.