Enhancing the efficiency of catalytic transfer hydrogenation in the production of γ-valerolactone from biomass with metal-organic frameworks supported by ruthenium-substituted phosphovanadomolybdic acid

Biomass is a promising raw material to prepare green solvent of γ -valerolactone (GVL). A series of Ru-substituted vanadium-containing polyoxometalates (POMs) of Ru n /3 H 4- n PMo 11 VO 40 ( n  = 1, 2, 3, 4) and Ru n /3 H 5- n PMo 10 V 2 O 40 ( n  = 1, 2, 3, 4, 5) were prepared, which were loaded on metal organic frameworks (MOFs) to afford POMs@MOF with adjusting strong oxidizing abilities. This paper focused on the effects of POMs@MOF on improving the yield and selectivity of GVL in a green system of formic acid (FA) and water. When cellulose, glucose, and levulinic acid (LA) were used as substrates, the yields of GVL were 43.2 %, 69.7 %, and 98.3 % with the selectivity of 48.0 %, 71.9 %, and 99.3 %, respectively. The results indicate that the strong oxidizing ability of POMs favors the conversion of biomass to GVL. The proposed catalytic system greatly reduces the use of noble metal Ru while enhancing the catalytic transfer hydrogenation performances. The adjustment of the proportion of Ru in POMs can provide efficient and promising catalytic systems for one-pot production of GVL from biomass with different structures.