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Exploring Hydrothermally Grown Potassium Titanate Fibers by STEM-in-SEM/EDX and XRD

Published online by Cambridge University Press:  14 July 2006

Wilhelm Habicht ,
Nikolaos Boukis ,
Günter Franz ,
Olaf Walter  and
Eckhard Dinjus
Wilhelm Habicht
Affiliation:
Forschungszentrum Karlsruhe, Institut für Technische Chemie, ITC-CPV, P.O. Box 3640, D-76021 Karlsruhe, Germany
Nikolaos Boukis
Affiliation:
Forschungszentrum Karlsruhe, Institut für Technische Chemie, ITC-CPV, P.O. Box 3640, D-76021 Karlsruhe, Germany
Günter Franz
Affiliation:
Forschungszentrum Karlsruhe, Institut für Technische Chemie, ITC-CPV, P.O. Box 3640, D-76021 Karlsruhe, Germany
Olaf Walter
Affiliation:
Forschungszentrum Karlsruhe, Institut für Technische Chemie, ITC-CPV, P.O. Box 3640, D-76021 Karlsruhe, Germany
Eckhard Dinjus
Affiliation:
Forschungszentrum Karlsruhe, Institut für Technische Chemie, ITC-CPV, P.O. Box 3640, D-76021 Karlsruhe, Germany
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Abstract

During lab-scale experiments on the reforming of methanol by means of water at supercritical conditions (T > 374°C, p > 22.1 MPa), a tubular reactor with a titanium liner was exposed to an aqueous solvent containing methanol (5 wt%) and KHCO3 (0.3 wt%). At the end of the run, a fibrous precipitate was found at two positions in the reactor. The material was studied in a field emission scanning electron microscope equipped with an energy dispersive X-ray analysis unit (FESEM/EDX). A thin-film support technique using carbon-filmed TEM grids was applied to perform scanning transmission-type imaging (STEM-in-SEM operation) and transmission current measurements. The analysis of the hydrothermally grown fibers resulted in a potassium titanate species composed of approximately K2TiO3, which has been confirmed by X-ray diffraction (XRD).

Keywords

FESEMSTEM-in-SEMEDXXRDpotassium titanatehydrothermal synthesis
Type
MODERN DEVELOPMENTS AND APPLICATIONS IN MICROBEAM ANALYSIS
Information
Microscopy and Microanalysis , Volume 12 , Issue 4 , August 2006 , pp. 322 - 326
Copyright
© 2006 Microscopy Society of America

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