Dehydration of Methanol to Dimethyl Ether Employing Modified H-ZSM-5 Catalysts

Khandan, N.; Kazemeini, M.; Aghaziarati, M.

Dehydration of Methanol to Dimethyl Ether Employing Modified H-ZSM-5 Catalysts

Document Type : Full article

Authors

N. Khandan ¹

M. Kazemeini ²

M. Aghaziarati ³

¹ Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Ave, Tehran, Iran

² Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Ave, Tehran, Iran.

³ Department of Chemistry and Chemical Engineering, Faculty of Materials, Malek Ashtar University of Technology, Lavizan, Tehran, Iran

Abstract

Synthesis of Dimethyl ether from methanol was investigated over H-ZSM-5 and promoted H-ZSM-5 catalysts employing Mg, Na, Zr, Al and Zn components. All samples were characterized by AAS, BET, XRD and TPD analyses. Results of TPD
analysis indicated that the number of weak strength acid sites increased on the surface of Na, Zn and Mg modified H-ZSM-5, while the number of medium strength acid sites increased on the surface of Zr and Al modified H-ZSM-5. Zr- modified H-ZSM-5 zeolite exhibited higher activity (94%) and selectivity (99%) than other materials while all modified catalysts exhibited good stability. Ultimately, it was concluded that production of dimethyl ether from methanol occurred
on acidic sites with medium and/or weak strengths. In this direction, an optimum catalyst for dehydration of methanol to DME with high conversion, selectivity and stability was developed.

Keywords

Dehydration

methanol

dimethyl ether

H-ZSM-5