Hydroxyapatite as a novel support for Ru in the hydrogenation of levulinic acid to γ-valerolactone

Kinetics of the ruthenium‐catalyzed hydrogenation of levulinic acid to γ‐valerolactone in aqueous solutions

“…LA conversion after 1 h was maximized (54 %) at T = 353 K. It was obvious that Ru/C facilitated hydrogenation of the substrate. To enable a comprehensive analysis, the outcome of previous works using heterogeneous Ru‐based catalysts is also shown in Table .…”

Vapor phase hydrogenation of aqueous levulinic acid over hydroxyapatite supported metal (M = Pd, Pt, Ru, Cu, Ni) catalysts.

“…of RuCl 3 .xH 2 O on HAP (Ru/HAP), resulted in the increase of acidity by four times and 10% decrease in the basicity compared to HAP ( Table 3). The enhanced acidity of Ru/HAP may probably be due to traces of chloride moiety present on the catalyst [19]. The FT-IR spectra (SI, Fig.…”

“…Recently, Upare et al reported 98.6% yield of ␥-valerolactone over Ru/C catalyst using dioxane as a solvent at high H 2 pressures [18]. Earlier we have shown a gVL rate of 15 mol h −1 (mol Ru ) −1 at moderate temperature over Ru/HAP at 5 bar H 2 pressure [19]. The high hydrogenation activity of Ru/HAP has prompted us to explore it further at ambient pressure for the conversion of LA to gVL.…”

“…(iv) It has also been explored as a catalyst support for gold and ruthenium in the water gas shift reaction as well as a stand-alone catalyst for the dehydrogenation and dehydration of alcohols [22][23][24][25]. In the present study, LA hydrogenation has been carried out under kinetic regime at atmosphere pressure in the temperature range of 275-425 • C. The reaction pathway from LA to gVL is dependent upon the catalyst acidity and hydrogenation activity of metal [19]. The multiple pathways reported are: (i) hydrogenation of LA via ␥-hydroxyvaleric acid, as an intermediate compound in equilibrium with gVL and (ii).…”

Role of Brønsted and Lewis acid sites on Ni/TiO2 catalyst for vapour phase hydrogenation of levulinic acid: Kinetic and mechanistic study

“…Ruthenium based homogeneous catalysts were reported with molecular hydrogen or formic acid as hydrogen source which showed good selectivity towards GVL formation [16][17]. Earlier we have explored hydroxyapatite supported Ru catalysts for the hydrogenation of LA and achieved 99% of GVL yield at 0.5 MPa H 2 pressure [18]. The hydrogenation of LA is reported with high GVL yields using 5% Ru/C catalyst at 130 °C and 1.2 MPa hydrogen pressure [19].…”