The role of defect sites and oxophilicity of the support on the phenol hydrodeoxygenation reaction

Highly selective conversion of phenol to cyclohexanol over Ru/Nb2O5-nC18PA catalysts with increased acidity in a biphasic system under mild conditions

“…The formation of O-Nb-O-P bonds 50 (Fig. S6 †) and the binding of H in C18PA to O in Nb 2 O 5 would result in an increase in incompletely coordinated Nb 5+ on the support, thus forming more oxygenophilic sites, 51,52 i.e., an increase in Lewis acid sites. 53 At the same time, there is a small increase in Brønsted acid because only a small fraction of OH is retained by C18PA after binding to the support.…”

Hydrodeoxygenation of Lignin-Derived Compound Mixtures on Pd-Supported on Various Oxides

“…In contrast, supports that possess oxophilic sites (e.g., ZrO 2 , TiO 2 , and Nb 2 O 5 ) promote activating and hydrogenating of the CO bond in the keto tautomer intermediate, thereby producing an unsaturated alcohol with further dehydration to aromatic compounds. 11,[15][16][17][18][19][20]24,27 For the HDO of anisole, deoxygenation is proposed to occur via two reaction pathways: (a) demethylation producing a surface phenoxy species, which is further hydrogenated in steps, first to phenol and then to benzene, and (b) direct demethoxylation to benzene. Transalkylation in anisole as well as in m-cresol is also possible to occur over acid catalysts.…”

Hydrodeoxygenation of benzyl alcohol on transition-metal-containing mixed oxides catalysts derived from layered double hydroxide precursors

“…The removal of oxygenated moieties requires the two catalytic functions to work either independently or cooperatively [5]. Noble metals such as Pd, Pt and Ru are known for their hydrogen activation function, and were used for HDO of phenolic bio-oil components such as phenols, guaiacols, syringols [5][6][7][9][10][11][12][13] and benzaldehyde [14,15]. Some studies used catalysts combining noble and transition metals, such as supported Rh-Co in the HDO of anisole and biodiesel [4] or Ru-Fe in supported ionic liquid phase catalysts in HDO of aromatic substrates containing carbonyl groups [16].…”