Synthesis of Tungstophosphoric Acid Incorporated Mesoporous Alumina Catalysts for Methanol Dehydration in DME Synthesis

Şener, M İlker
Sezgi, Naime Aslı
Doğu, Timur
Doğu, Güşen
Oktar, Nuray
Dimethyl ether (DME) is considered as a highly promising environmentally clean diesel fuel alternate, which can be produced from synthesis gas. It has high cetane number (55-60) and clean burning properties [1]. Possibility of using CO2 as the carbon source in DME production makes this process even more attractive as a carbon neutral technology. Production of DME from synthesis gas requires a bifunctional catalyst combination, for methanol synthesis and dehydration functions. As for the methanol synthesis function, commercial Cu-ZnO based catalysts are available. Heteropolyacids with very high Bronsted acidity are considered as highly promising catalytic materials for dehydration of methanol to DME [2, 3]. However, they have very low surface area [3]. In the present study, tungstophosphoric acid incorporated mesoporous alumina catalysts with high surface area and ordered pore structures were synthesized, to be used as the methanol dehydration catalysts in DME synthesis. Mesoporous alumina (MA) was synthesized by an evaporation-induced self-assembly (EISA) method [4], using Pluronic-123 as the surfactant. In order to improve dehydration activity of this material 5% TPA was impregnated on this material (MA), as well as on commercial g-alumina (Toyo). Nitrogen physisorption results exhibit Type IV isotherms for both MA (209.7m2 /g) and commercial Toyo (147.7m2 /g).Results revealed that impregnation of TPA did not cause significant change of the structure of commercial g-alumina and the synthesized materials had high acidity, which is required for methanol dehydration in DME synthesis.
The 6th Catalysis Conference, (27 - 30 Nisan 2016)


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Citation Formats
M. İ. Şener, N. A. Sezgi, T. Doğu, G. Doğu, and N. Oktar, “Synthesis of Tungstophosphoric Acid Incorporated Mesoporous Alumina Catalysts for Methanol Dehydration in DME Synthesis,” presented at the The 6th Catalysis Conference, (27 - 30 Nisan 2016), Türkiye, 2016, Accessed: 00, 2021. [Online]. Available: