Dimethyl Ether Synthesis over Novel Silicotungstic Acid Incorporated Nanostructured Catalysts

Date

2010-01-01

Author

Ciftci, Aysegul
VARIŞLI, DİLEK
Doğu, Timur

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Dimethyl ether (DME), which is an excellent green diesel-fuel alternate with excellent clean burning properties, is synthesized by dehydration of methanol over novel solid acid catalysts, which are synthesized following a direct hydrothermal route and using silicotungstic acid (STA) as the active compound. These mesoporous silicate structured catalysts have surface area values of 108-393 m(2)/g, depending upon their W/Si ratio. These catalysts showed very high methanol dehydration activity and also very high DME selectivity values, approaching 100%. The STA-SiO2 mesoporous nanocomposite catalyst having a W/Si atomic ratio of 0.33 showed the highest activity, with a DME selectivity over 99% and a methanol conversion over 60%, at 250 degrees C and at a space time of 0.27 s.g.cm(-3). Effects of W/Si atomic ratio, calcination temperature and the synthesis procedure on the catalytic performance of these novel mesoporous catalytic materials were investigated.

Subject Keywords

DME, Methanol, Dehydration, Silicotungstic acid, Mesoporous catalyst

URI

https://hdl.handle.net/11511/56051

Journal

INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

A. Ciftci, D. VARIŞLI, and T. Doğu, “Dimethyl Ether Synthesis over Novel Silicotungstic Acid Incorporated Nanostructured Catalysts,” INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING, pp. 0–0, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56051.