The One Step Oxidation of Methanol to Dimethoxymethane on V2O5/CeO2 Catalysts

The One Step Oxidation of Methanol to Dimethoxymethane on V₂O₅/CeO₂ Catalysts

Heqin Guo^a, Bo Hou^a, Litao Jia^a, Debao Li^a*

^a State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China.

*Corresponding author: Tel. /Fax: +86 351 4040410. E-mail addresses: dbli@sxicc.ac.cn

Dimethoxymethane (CH₃OCH₂OCH₃), as an important chemical intermediate, was widely used as diesel additive and building block in organic synthesis. Generally, DMM is produced by the two-stage synthesis. Such a flow chart could lead to a high cost, which inhibits the application of DMM. Compared with the two-step technique, the one-stage technique can synthesize DMM on the bi-founctional (employing redox sites and acidic sites) catalysts (3CH₃OH + 1/2O₂ °úCH₃OCH₂OCH₃ + 2H₂O). This technique is expected to avoid the drawback of the two-stage production.

In the present study, the V₂O₅/CeO₂ catalysts with different V₂O₅ content were prepared by the Sol-Gel method and characterized by XRD, BET, Raman, NH₃-TPD and H₂-TPR techniques. The catalytic properties were evaluated by the one-step oxidation of methanol to dimethoxymethane. The results showed that the vanadium was monolayer dispersed as V₂O₅ content was 15 wt%, aggregated as V₂O₅ crystalline above 20 wt% and formed CeVO₄ at 30 wt%. The higher dispersion of vanadium can lead to stronger reducibility and more acidic sites, which were closely related to the higher methanol conversion and dimethoxymethane (DMM) selectivity.

Keywords: Vanadia-cerium catalyst; Methanol oxidation reaction; Acidity; Redox; Dimethoxymethane