Effect of the Brønsted acidity on the behavior of CO2 methanol reaction

The CO2 methanol reforming reaction in liquid phase over Keggin type heteropoly compounds catalysts was investigated. The prepared catalysts, H3PMo12O40 and its copper salt Cu1.5PMo12O40 were characterized by means of IR, and TG. Catalysts tests were carried out at 0.12 MPa and at different temperatures. The effects of temperature and the catalyst amount were investigated. When the protons of H3PMo12O40 were replaced with copper cations, the activity decreased while the selectivity of dimethyl carbonate (DMC) increased slightly. Brønsted acid sites reduce the formation of DMC in favor of dimethyl ether (DME). When raising the reaction temperature, it was found that a lower temperature is favorable for DMC formation, and a maxima in the DMC formation was observed at 328 K.

Graphical abstractSeveral studies have demonstrated that the DMC can be obtained by the reaction of methanol with carbon dioxide:Figure optionsDownload full-size imageDownload as PowerPoint slideThe influence of Brønsted-acid sites on the behaviour of this reaction was investigated using Keggin-type heteropolyanions (HPA) as catalysts.