Effect of support modifications for CoMo/γ-Al2O3 and CoMo/ASA catalysts in the hydrodeoxygenation of guaiacol

• Guaiacol HDO was tested on CoMo/γ-Al2O3 and CoMo/ASA catalysts modified with Na.
• The catalysts modified with Na showed a decrease in their catalytic activity.
• The Na addition leads to a decrease in the acidity of the catalysts.
• Selectivity toward phenol increases with increasing amounts of Na on the support.
• The variation in Si/(Si + Al) molar ratio leads to changes mainly in activity.

CoMo catalysts supported on a commercial alumina (γ-Al2O3) modified with Na (1, 2 and 3 wt.%) and supported on amorphous aluminosilicates (ASA) with different Si/(Si + Al) ratios (0.15, 0.25 and 0.75) were prepared. Additionally, a CoMo catalyst supported on ASA modified with 3 wt.% Na was synthetized. These catalysts were evaluated in the hydrodeoxygenation (HDO) of guaiacol (2-methoxyphenol) as bio-oil model compound. The results show a decrease of catalytic activity with increasing amounts of Na added compared to an unmodified catalyst. This modification in the acid–base properties of the catalyst generates changes in selectivity such as the inhibition of methylated compounds formation, e.g., cresol and the increase of phenol production. For ASA-supported catalysts, a decrease in catalytic activity with the increase in the Si content took place, whereas the HDO degree was not significantly affected. Moreover, the ASA-supported catalysts led to a lower activity of the HDO of guaiacol compared to γ-Al2O3-supported catalysts.

Figure optionsDownload high-quality image (537 K)Download as PowerPoint slide