The effect of nickel precursors and the temperature annealing to obtain intermetallic Ni3Sn2 alloy catalysts on its activity and selectivity in the selective hydrogenation of biomass-derived furfural (FFald) were investigated. Two types of nickel precursors (c.a., i) nickel metal (Ni°) derived from Raney®nickel and ii) nickel ion (Ni2+) derived from nickel chloride) were employed as the starting materials via hydrothermal at 423 K for 24 h followed by reduction with H2 at the elevated temperature of 573-873 K for 1.5 h. The physico-chemical properties of the intermetallic Ni3Sn2 were characterized by XRD, N2-, and H2-adsorption, ICP-AES, and NH3-TPD. The intermetallic Ni3Sn2 alloy catalysts, both bulk and supported, demonstrated high activity and selectivity towards hydrogenation of FFald. The activity and selectivity of g-Al2O3 and AA-supported Ni3Sn2 alloy catalysts in the hydrogenation of FFald to furfuryl alcohol (FFalc) were maintained even after annealing at up to 873 K, but that of bulk Ni3Sn2 drastically dropped. Ni-Sn alloy catalysts which were obtained from Raney®Ni precursor showed more stable than that of nickel salts during hydrogenation of furfural to furfuryl alcohol. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Bimetallic palladium-tin catalysts supported on microporous carbon (denoted as Pd-Sn(x)/C, loading amount of Pd = 5 wt% and x = Pd/Sn molar ratio; c.a. 3.0; 1.5; and 1.0) showed high selectivity in the hydrogenation of stearic acid towards 1-octadecanol (stearyl alcohol) under mild reaction conditions. Pd-Sn(x)/C catalysts were synthesized via the hydrothermal method at temperature of 150 °C for 24 h, and reduced with H2 at 400 °C for 3 h. Pd-Sn(1.5)/C catalyst exhibited the highest yield of stearyl alcohol (1-octadecanol) (up to 73.2%) at 100% conversion of stearic acid at temperature 240 °C, initial H2 pressure of 3.0 MPa, a reaction time of 13 h, and in 2-propanol/water solvent. The high selectivity of alcohols over Pd-Sn(1.5)/C catalyst can be attributed to the formation of bimetallic Pd-Sn alloy phases (e.g. Pd3Sn and Pd3Sn2) as obviously depicted by XRD analysis. The presence of co-promotor Sn and the formation of bimetallic may play a pivotal role in the high selectivity of 1-octadecanol. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The bulk Ni3Sn2 alloy catalysts exhibited highly active and selective for de/hydration–hydrogenation of biomass-derived furfural to produce 1,4-pentanediol (87%) without the acidic co-catalyst.

Supported bimetallic palladium-tin catalyst on gamma-alumina (γ-Al2O3) (denoted as Pd–Sn(3.0)/γ-Al2O3; Pd = 5%wt and Pd/Sn molar ratio is 3.0) has been synthesized via the hydrothermal method at a temperature of 423 K for 24 h and reduced with H2 at 673 K for 3 h. The XRD patterns of the samples showed typical diffraction peaks of support γ-Al2O3, metallic Pd, Sn, and Pd–Sn alloy phases. Diffraction peaks of metallic Pd were observed at 2θ = 39.8°; 46.6°; and 68.0°, which can be attributed to the Pd(111), Pd(200), and Pd(220), respectively, while the diffraction peaks at 2θ = 39.8° and 41.0° can be attributed to Pd2Sn and Pd3Sn2, respectively, which may overlap with the Pd(111) species. The ammonia desorption and pyridine adsorption profiles showed Lewis and Brönsted acid sites. The specific surface area (SBET) of Pd–Sn(3.0)/γ-Al2O3 catalyst was 117.83 m2/g which is dominated by a micropore structure. The highest conversion of stearic acid was 99.1% with a yield of 1-octadecanol 43.2% was obtained at temperature 513 K, initial H2 pressure of 2.0 MPa, a reaction time of 13 h, and in 2-propanol/water (4.0:1.0 v/v) solvent.