Preparation of nano-Ni/meso-Ce–TiO₂ by one-step in a sol–gel system and its catalytic performance for hydrogenolysis of xylitol

Abstract

The conventional method for the preparation of metal nanoparticles loaded on a mesoporous metal oxide is tedious, and its chemical and physical properties cannot be optionally controlled. A simple and convenient method by one-step in the AcHE sol-gel system was employed for the preparation of nano-Ni/meso-Ce-TiO 2 samples with different Ni nanoparticle loadings. Their physical and chemical properties were characterized by XRD, liquid N 2 adsorption-desorption, EDX, ICP, FT-IR, H 2 -TPR and TEM techniques, and their catalytic performance was investigated in the hydrogenolysis of xylitol. The results show that these samples with ordered mesoporous structures, uniform pore size and large specific surface area can be obtained. The Ni nanoparticles can be well dispersed on the mesoporous Ce-TiO 2 surface. The stability of the Ni nanoparticles on the mesoporous TiO 2 would be promoted by the introduction of a small amount of cerium species. The 8% nano-Ni/meso-Ce-TiO 2 sample shows a higher catalytic performance than other samples. The conversion of xylitol was 87.9% and a total yield of diols of 83.2% can be reached. It shows high stability, and the conversion of xylitol and the total yield of diols decreased slightly after repeating the reaction 8 times. The method provides a valuable reference for the preparation of metal nanoparticles loaded on a mesoporous metal oxide, especially for nonnoble metal nanoparticles.

Catalytic Deoxygenation of Xylitol to Renewable Chemicals: Advances on Catalyst Design and Mechanistic Studies

“… XRD patterns for (a) Cu/SiO 2 [38] ((a) Cu/SiO 2 treated with Ca(OH) 2 solution at 473 K; (b) Cu/SiO 2 after a one run; (c) spent Cu/SiO 2 after three runs; (d) spent Cu/SiO 2 after four runs; (e) the sample in (d) was re‐calcined; (f) the sample in (e) was reduced. ), (b) Ni/Ce−TiO 2 [37] (a and f: 623 K, b: 673 K, c: 723 K, d: 773 K, e: 823 K), (c) Ni−Cu/SiO 2 [36] ((a) reduced Ni−Cu/SiO 2 , (b) used Ni−Cu/SiO 2 after 5 runs, (c) reduced Cu/SiO 2 , (d) used Cu/SiO 2 after 5 runs.…”

“…NiÀ Ce/TiO 2 . Zhou et al [37] studied xylitol hydrogenolysis with NiÀ Ce/TiO 2 catalysts at 200°C and 8 MPa H 2 pressure, prepared by sol-gel method, with very high yield of glycols (83.2 %). The SEM and TEM images of NiÀ Ce/TiO 2 sample are shown in Figure 10.…”

“…Surface characterization of various catalysts for hydrogenolysis of xylitol. SEM image of (a) Ni/Ce-TiO 2 ; [37] TEM image of (b) Ni/C; [34] Electron mapping images of (c-e) Ni/Ce-TiO 2 ; [37] TEM image of (f) Cu/SiO 2 ; [38] SEM image of (g) Cu/SiO 2 ; [38] TEM image of (h) NiÀ Cu/ZrO 2 ; [35] [38] in NiÀ Cu/SiO 2 catalysts. Zhu et al [39] enhanced the Cu based catalysts stability.…”

“…NiÀ Cu/SiO 2 catalysts exhibit the peak of CuÀ Ni alloy (see Figure 11 XRD patterns for (a) Cu/SiO 2 [38] ((a) Cu/SiO 2 treated with Ca(OH) 2 solution at 473 K; (b) Cu/SiO 2 after a one run; (c) spent Cu/SiO 2 after three runs; (d) spent Cu/SiO 2 after four runs; (e) the sample in (d) was re-calcined; (f) the sample in (e) was reduced. ), (b) Ni/CeÀ TiO 2 [37] (a and f: 623 K, b: 673 K, c: 723 K, d: 773 K, e: 823 K), (c) NiÀ Cu/SiO 2 [36]…”

Selective Hydrogenolysis of Biomass‐Derived Xylitol to Glycols: Reaction Network and Kinetics

“…platinum, ruthenium, copper, cerium, and nickel, as active species, various bimetallic and trimetallic catalysts on different supports, i.e., activated carbon, TiO 2 , Al 2 O 3 , or SiO 2 , are mentioned. Examples of these catalysts are Cu/SiO 2 21, 22, Ni/C 23–25, Ni/Al 2 O 3 26, 27, Ni/TiO 2 28, Pt/C 25, 29, Ru/C 25, 26, 30–33, Cu‐CaO/Al 2 O 3 34, 35, Ni‐Cu/SiO 2 36, Ni‐Re/C 37, 38, Ru‐Re/C 34, and Ni‐Cu‐Ag/C 39, whereby NaOH, KOH, MgO, Ba(OH) 2 , or Ca(OH) 2 were used as basic promotors.…”