Chauruka, SR, Hassanpour, A, Brydson, R et al. (3 more authors) (2015) Effect of mill type on the size reduction and phase transformation of gamma alumina. Chemical Engineering Science, 134. 774 - 783. ISSN 0009-2509
Abstract
The influence of stress modes and comminution conditions on the effectiveness of particle size reduction of a common catalyst support; γ-Alumina is examined through a comparative assessment of three different mill types. Air jet milling is found to be the most effective in reducing particle size from a d90 of 37 µm to 2.9 µm compared to planetary ball milling (30.2 µm) and single ball milling (10.5 µm). XRD and TEM studies confirm that the planetary ball mill causes phase transformation to the less desired α-Alumina resulting in a notable decrease in surface area from 136.6 m2/g to 82.5 m2/g as measured by the BET method. This is consistent with the large shear stresses under high shear rates prevailing in the planetary ball mill when compared to the other mill types. These observations are consistent with a shear-induced phase transformation mechanism brought about by slip on alternate close packed oxygen layers from a cubic close packed to a hexagonal close packed structure.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). |
Keywords: | Gamma alumina; Planetary ball milling; XRD; Phase transformation |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Institute for Particle Science and Engineering (Leeds) The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Institute for Materials Research (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 31 Jul 2015 14:01 |
Last Modified: | 26 Feb 2019 09:32 |
Published Version: | http://dx.doi.org/10.1016/j.ces.2015.06.004 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.ces.2015.06.004 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:88677 |