Insights in supported rhenium carbide catalysts for hydroconversion of lignin-derived compounds

Rhenium supported over activated carbon (AC) was carburized under different temperatures (from 500 to 700 degrees C) under a mixture of H-2/C2H4 (75/25). Resulting catalysts were characterized by N(2-)sorption, CO chemisorption, temperature programed reduction (TPR), ammonia temperature programed desorption (TPD-NH3), STEM, and XPS and catalytic properties were measured in a batch reactor at 350 degrees C, 5.0 MPa for the hydrodeoxygenation (HDO) of guaiacol. Results have shown that Rhenium was gradually reduced and carburized upon increasing the temperature. From 650 degrees C, a RexC phase was obtained and transformed into ReC at 700 degrees C. RexC was the most active phase obtained and maximum yield in benzene of 51% was reached at complete conversion. ReC phase showed to inhibit the hydrogenolysis of phenol into benzene.