The Promoting Effect of Ti on the Catalytic Performance of V-Ti-HMS Catalysts in the Selective Oxidation of Methanol

The effects of Ti modification on the structural properties and catalytic performance of vanadia on hexagonal mesoporous silica (V-HMS) catalysts are studied for selective methanol-to-dimethoxymethane oxidation. Characterizations including N-2 adsorption-desorption (S-BET), X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS UV-Vis), Micro-Raman spectroscopy, FTIR spectroscopy, and H-2 temperature-programmed reduction (H-2-TPR) were carried out to investigate the property and structure of the catalysts. The results show that Ti can be successfully incorporated into the HMS framework in a wide range of Si/Ti ratios from 50 to 10. Ti modification can effectively improve the distribution of vanadium species and thus enhance the overall redox properties and catalytic performance of the catalysts. The catalytic activity of the V-Ti-HMS catalysts with the Si/Ti ratio of 30 is approximately two times higher than that of V-HMS catalysts with comparable selectivity. The enhanced activity exhibited by the V-Ti-HMS catalyst is attributed to the improved dispersion and reducibility of vanadium oxides.

Automated summary

The study found that Ti modification can effectively improve the distribution of vanadium species, enhancing the overall redox properties and catalytic performance of V-HMS catalysts. The catalytic activity of V-Ti-HMS catalysts is approximately two times higher than that of V-HMS catalysts, attributed to the improved dispersion and reducibility of vanadium oxides.