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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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References

REFERENCES

ASME Steam Tables. (1992). 6th ed. New York: American Society of Mechanical Engineers.Google Scholar
Bao, N., Feng, X., Lu, X., & Yang, Z. (2002). Study of the formation and growth of potassium titanate whiskers. J Mater Sci 37, 3035–3043.CrossRefGoogle Scholar
Boukis, N., Diem, V., Habicht, W., & Dinjus, E. (2003). Methanol reforming in supercritical water. Ind Eng Chem Res 42, 728–735.CrossRefGoogle Scholar
Boukis, N., Franz, G., Habicht, W., & Dinjus, E. (2001). Corrosion resistant materials for SCWO-applications. Experimental results from long-time experiments. In Corrosion 2001, pp. 1–6. Houston, TX: NACE International.Google Scholar
CRC Handbook of Chemistry and Physics. (1980). 60th ed. Boca Raton, FL: CRC Press.Google Scholar
Habicht, W., Boukis, N., Franz, G., & Dinjus, E. (2004). Investigation of nickel-based alloys exposed to supercritical water environments. Microchim Acta 145, 57–62.CrossRefGoogle Scholar
Kruse, A. & Gawlik, A. (2003). Biomass conversion in water at 330–410°C and 30–50 MPa. Identification of key compounds for indicating different chemical reaction pathways. Ind Eng Chem Res 42, 267–279.Google Scholar
Sinag, A., Kruse, A., & Rathert, J. (2003). Influence of the heating rate and type of catalyst on the formation of key intermediates and on the generation of gases during hydropyrolysis of glucose in supercritical water in a batch reactor. Ind Eng Chem Res 43, 502–508.Google Scholar
Watt, I.M. (1997). The Principle and Practice of Electron Microscopy. Cambridge, UK: Cambridge University Press.CrossRefGoogle Scholar
Yahya, R.B., Hayashi, H., Nagase, T., Ebina, T., Onodera, Y., & Saitho, N. (2001). Hydrothermal synthesis of potassium hexatitanates under subcritical and supercritical water conditions and its application in photocatalysis. Chem Mater 13, 842–847.CrossRefGoogle Scholar
Yang, Q., Wang, P., Li, Y., Yin, Q., Werner, P.-E., Moliterni, A., & Cheng, Y.-B. (2004). On the superstructure of KTiO2(OH). Z Kristallogr 219, 227–230.CrossRefGoogle Scholar
Yuan, Z.-Y., Zhang, X.-B., & Su, B.-L. (2004). Moderate hydrothermal synthesis of potassium titanate nanowires. Appl Phys A 78, 1063–1066.CrossRefGoogle Scholar