Production of pentyl valerate from γ-valerolactone, pentanol and H₂ using Pd and Rh-based bifunctional catalysts

Abstract

Easily prepared SiO2–Al2O3-supported Rh and Pd-based catalysts exhibit high activity and selectivity in the pentyl valerate production in liquid phase from γ-valerolactone, pentanol and H2, reaching the highest reported productivity.

Valeric Biofuels from Biomass‐Derived γ‐Valerolactone: A Critical Overview of Production Processes

“…Based on our results over noble metal‐based catalysts, [60,61] a particular correlation between the Lewis proportion of the strong acid sites (outgassing the pyridine at 450 °C) and the PV selectivity (at X GVL =50 %) was observed, as Figure 7 shows. This is indicating that the strength of Lewis acid sites is relevant for the two acid‐catalyzed reactions.…”

“…In our opinion, though the first report of valeric esters production was in 2010, the conversion of GVL into valeric biofuels is still in an early stage. Only two years ago, some serious progress in the valeric ester productivity (300‐660 mmol g M −1 h −1 ) was observed in batch conditions, mainly when noble metal‐based catalysts (Pt, Rh and Pd) with moderate metal loadings (≅1 wt%) were tested in ROUTE 2 for PV production [60,61] . Pd‐based catalysts also showed interesting performances along ROUTE 1 but only when very high metal loading (5 wt%) and severe reaction conditions were employed [44] .…”

“…With all this knowledge and, with the aim of improving the PV productivity even more, our group prepared, characterized and tested SiO 2 −Al 2 O 3 ‐supported Rh and Pd‐based bifunctional catalysts with relatively low metal loading (≅1 wt%) [61] . The M 0 /SA catalysts exhibited a specific surface area and pore volume slightly lower than those of the SA support and the presence of metal nanoparticles with an average size of 5.6 nm for Rh/SA and 3.7 nm for Pd/SA.…”

“…Only two years ago, some serious progress in the valeric ester productivity (300-660 mmol g M À 1 h À 1 ) was observed in batch conditions, mainly when noble metal-based catalysts (Pt, Rh and Pd) with moderate metal loadings (ffi1 wt%) were tested in ROUTE 2 for PV production. [60,61] Pd-based catalysts also showed interesting performances along ROUTE 1 but only when very high metal loading (5 wt%) and severe reaction conditions were employed. [44] In this case, the PV productivity was slightly lower than 90 mmol g M À 1 h À 1 , which can be considered an intermediate value among the reported values (Table 2).…”

Supported rhenium catalysts for the hydrogenation of levulinic acid derivatives: limits and potential

“…60 In particular, the hydrogenation of GVL to PV in the liquid phase with pentanol as reactant/solvent has been investigated using noble metals supported on SiO 2 -Al 2 O 3 -and Cu-based catalysts. [61][62][63][64][65] The one-pot upgrading of GVL to PV was achieved with 60.6% of yield using a bifunctional 5% Pd/HY catalyst in a batch reactor system also without pentanol as reactant/solvent under relatively harsh conditions (260 °C, 80 bar of H 2 , 30 h, solvent noctane). 66 Herein, we report on the conversion of levulinic acid derivatives to 1-pentanol and/or pentyl valerate using a batch reactor in solvent-free conditions over Re-based catalysts.…”