High-Loading Nickel Phosphide Catalysts Supported on SiO₂–TiO₂ for Hydrodeoxygenation of Guaiacol

Abstract

High-loading Ni x P y catalysts supported on SiO 2 −TiO 2 binary oxides with different Si/Ti atomic ratios were prepared by liquid-phase phosphidation using triphenylphosphine (PPh 3 ) and valued for the hydrodeoxygenation (HDO) of guaiacol. The samples synthesized were characterized by N 2 adsorption, X-ray diffraction (XRD), transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), and ammonia temperature-programmed desorption. The XRD and XPS results showed that the Ni 2 P/Ni 12 P 5 mixed phase was formed when SiO 2 −TiO 2 binary oxides were employed as supports, whereas only Ni 2 P and Ni 12 P 5 phases were produced on SiO 2 and TiO 2 single oxides, respectively. XPS analysis showed that TiO 2−x species were generated on the surface of the catalyst during the reduction of the precursor, and the electron transfer occurred from TiO 2−x species to the Ni x P y surface. TiO 2−x species on the Ni x P y surface would contribute to the high HDO activity of guaiacol on Ni x P y catalysts because the presence of TiO 2−x species promoted the adsorption of guaiacol and activation of the C−O bond in the guaiacol molecule. HDO reaction of guaiacol on Ni x P y catalysts dramatically followed the hydrogenation path owing to the high hydrogenation activity of Ni x P y catalysts.

Ti3+ Tuning the Ratio of Cu+/Cu0 in the Ultrafine Cu Nanoparticles for Boosting the Hydrogenation Reaction

“…After fitting, one set of peaks at 459.1 and 464.5 eV can be assigned to Ti 3+ ions and another set of peaks at 459.9 and 465.9 eV are assigned to Ti 4+ ions. [38] The coexistence of Ti 3+ and Cu + from the XPS of reduced Ti-doped samples further suggest the formation of Ti 3+ O V Cu + bonds during the reduction of Ti 4+ OCu 2+ bonds. [39][40][41] Moreover, the ratio of Ti 3+ /(Ti 4+ +Ti 3+ ) in the three Ti-doped samples are similar, 41.2%, 39.6%, and 40.4% for Cu/ Ti(0.2)-SiO 2 , Cu/Ti(0.4)-SiO 2 , and Cu/Ti(0.6)-SiO 2 , respectively (Table S2, Supporting Information).…”

Nickel phosphide nanoalloy catalyst for the selective deoxygenation of sulfoxides to sulfides under ambient H2 pressure

“…Subsequently, the spillover hydrogen diffuses onto the TiO2 surface (II), where it reduces TiO2 to form an Ov site (III). 62,63 The Ov site in TiO2 deoxygenates the sulfoxide to give a sulfide (IV), thereby completing the catalytic cycle. The cooperative effects of nano-Ni2P and TiO2 play key roles in the activation of H2 followed by the formation of Ov sites and the deoxygenation of sulfoxide, respectively.…”

Catalytic Hydrodeoxygenation of Model Bio‐oils Using HZSM‐5 and Ni2P/HZM‐5 Catalysts: Comprehension of Interaction

“…These undesired properties can be ameliorated by catalytic hydrodeoxygenation (HDO) [7]. In previous studies, most researchers paid attention to HDO of a single model compound to imitate bio-oil upgrading, which involved ketones (acetone [8], 2-furyl methyl ketone [9]), carboxylic acids (acetic acid [10]), phenols (guaiacol [11,12], phenol [13]), furans (2-methylfuran [14]), aldehydes (furfural [15]) etc.…”