Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.524150
Title: Hydrogen desorption and absorption for activated magnesium hydride
Author: Prendergast, James W.
Awarding Body: University of Birmingham
Current Institution: University of Birmingham
Date of Award: 2010
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Abstract:
The interaction between MgH2 and LiBH4 was studied to determine the resultant effects on hydrogen desorption and absorption kinetics for potential use as a hydrogen storage material. It is found that the addition of LiBH4 in small molar ratios results in improved kinetics of the same order as those observed for mechanically milled magnesium. The mixture of MgH2 + LiBH4 in ratios at and below 4:1, once reacted, is a highly reversible material at 300°C and it is observed that the kinetics improve upon the process of hydrogen cycling. This improvement is partially attributed to a refinement in microstructure that results in highly porous particle agglomerates and it is this feature that is likely to have a large effect on the kinetics of hydrogenation due to the rate limiting step of the reaction being hydrogen diffusion into the particles of Mg which can be coated in MgH2 phase, through which H2 does not diffuse easily. Additionally it is observed via Raman spectroscopy that a new bonding structure exists in the H2 cycled mixture after desorption which might improve the rehydrogenation of the sample and reduce the enthalpy of decomposition through an intermediate reaction pathway.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.524150  DOI: Not available
Keywords: QD Chemistry
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