A promising approach to transform levulinic acid into γ-valerolactone using niobic acid photocatalyst and the accumulated electron transfer technique

Photo–Thermo-Dual Catalysis of Levulinic Acid and Levulinate Ester to γ-Valerolactone

“…Monitored by gas chromatography–mass spectrometry (GC–MS), LA was hydrogenated and dehydrated into an acetyl propionyl radical, which was further hydrogenated and cyclized to GVL. Recently, Oliveira and co-workers reported that commercial niobic acid (Nb 2 O 5 ·nH 2 O; HY-340) is a promising photocatalyst for the hydrogenation of LA to GVL using ethanol as a hydrogen donor . The authors proposed that the major reaction pathways could involve the formation of ethyl levulinate (EL) and 6-hydroxy heptane 2,5-dione (HHD), which is consistent with Zhu’s report .…”

“…No product was observed under the photocatalytic process, although the reaction time was prolonged to 24 h (Scheme b). These results indicated that the photocatalytic hydrogenation of aliphatic ketone did not occur on Pt/TiO 2 either because the catalyst does not have sufficient negative potential to reduce 2-heptanol , or due to the weak interaction between the carbonyl group of aliphatic ketone and the catalyst. , …”

Catalytic valorisation of biomass levulinic acid into gamma valerolactone using formic acid as a H2 donor: a critical review

“…164 Photo catalysts reported in literature were evaluated using isopropanol, ethanol, and 2-propanol as H 2 donor. [155][156][157]165 These studies should direct toward testing FA decomposition for in situ H 2 production in the presence of photo catalyst.…”

“…153 Interestingly, higher value solvents derived from biomass such as GVL can be successfully produced from LA using niobic acid photo catalyst using UV-assisted accumulated electron transfer technique. 154 Moreover, TiO 2 doped with Pt is suggested as a promising catalyst that features a dual role in the production of GVL from LA and levulinate esters using alcohol as H 2 source and under mild reaction conditions. In brief, the catalyst showed a high GVL yield of 93% for thermocatalytic route using 2-propanol solvent but lower yields for photocatalytic one.…”

Selective methane photooxidation into methanol under mild conditions promoted by highly dispersed Cu atoms on crystalline carbon nitrides

“…S12c, ESI †), according to EPR, explaining the higher yield in methanol production. In addition, oxygenate liquids, such as methanol, can be found in the solution for prolonged periods, as described by EPR assays with methanol and PBN, 22 which detects the adduct methoxy-PBN only for Cu-PHI (Fig. 3d and Fig.…”