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In situ synchrotron diffraction of the electrochemical reduction pathway of TiO2

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Bhagat, R. (Rohit), Dye, D., Raghunathan, S. L., Talling, R. J., Inman, D. (Douglas), Jackson, B. K., Rao, K. K. (Kartik K.) and Dashwood, R. J.. (2010) In situ synchrotron diffraction of the electrochemical reduction pathway of TiO2. Acta Materialia, Vol.58 (No.15). pp. 5057-5062. ISSN 1359-6454

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Official URL: http://dx.doi.org/10.1016/j.actamat.2010.05.041

Abstract

Despite over ten years of work into the low-cost electrowinning of Ti direct from the oxide, the reduction sequence of TiO2 pellets in molten CaCl2 has been the subject of debate, particularly as the reduction pathway has been inferred from ex situ studies. Here, for the first time white beam synchrotron X-ray diffraction is used to characterize the phases that form in situ during reduction and with similar to 100 mu m resolution. It is found that TiO2 becomes sub-stoichiometric very early in reduction, facilitating the ionic conduction of O ions, that CaTiO3 persists to nearly the end of the process and that, finally, CaO forms just before completion of the process. The method is quite generally applicable to the in situ study of industrial chemical processes. Implications for the industrial scale-up of this method for the low-cost production of Ti are drawn.

Item Type:	Journal Article
Subjects:	Q Science > QD Chemistry T Technology > TA Engineering (General). Civil engineering (General) T Technology > TP Chemical technology
Divisions:	Faculty of Science > WMG (Formerly the Warwick Manufacturing Group)
Library of Congress Subject Headings (LCSH):	Titanium -- Electrometallurgy
Journal or Publication Title:	Acta Materialia
Publisher:	Pergamon
ISSN:	1359-6454
Date:	September 2010
Volume:	Vol.58
Number:	No.15
Number of Pages:	6
Page Range:	pp. 5057-5062
Identification Number:	10.1016/j.actamat.2010.05.041
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Restricted or Subscription Access
Funder:	United States. Defense Advanced Research Projects Agency (DARPA), United States. Office of Naval Research, Engineering and Physical Sciences Research Council (EPSRC)
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URI:	http://wrap.warwick.ac.uk/id/eprint/5439