“H2-free” demethoxylation of guaiacol in subcritical water using Pt supported on N-doped carbon catalysts: A cost-effective strategy for biomass upgrading

Abstract

“H2-free” HDO is a revolutionary route to circumvent the limitations of H2-fed HDO reactors for biomass upgrading. This work demonstrates the viability of this economically appealing route when an adequate catalyst is implemented. Herein, we have developed a new family of Pt catalysts supported on N-doped activated carbons for the H2-free HDO process of guaiacol. Several N-donors have been used to tune the catalyst's structural and electronic properties. As a general trend, the N-promoted samples are more selective towards oxygen-depleted products. The best performing material, namely Pt/PANI-AC, reached outstanding guaiacol conversion values – ca. 75% at 300 °C while displaying reasonable stability for multiple recycling operations. The advanced performance is ascribed to the modified electronic and acid-base properties which favor guaiacol activation and C−O cleavage, as well as the excellent dispersion of the Pt nanoparticles.