Formic acid assisted hydrogenation of levulinic acid to $$\upgamma $$ γ -valerolactone over ordered mesoporous $$\hbox {Cu/Fe}_{2}\hbox {O}_{3}$$ Cu/Fe 2 O 3 catalyst prepared by hard template method

Abstract

Vapor phase hydrogenation of levulinic acid using formic acid as a hydrogen source has been conducted over ordered mesoporous $$\hbox {Cu/Fe}_{2}\hbox {O}_{3}$$ catalysts prepared by hard template method using mesoporous silica, SBA-15. X-ray diffraction result reveals the absence of copper peaks because of either highly dispersed state, or formation of a solid solution with iron oxides. The $$\hbox {N}_{2}$$ sorption analysis and TEM results indicate the retainment of mesoporous nature in the samples. Among the catalysts tested, 10 (wt%) $$\hbox {Cu/Fe}_{2}\hbox {O}_{3}$$ seems to be an efficient catalyst to yield higher amounts of $$\upgamma $$ -valerolactone under hydrogen-free conditions. The results reveal the formation of spinel species, which gets reduced easily at a lower temperature (as evidenced from TPR studies), and as a consequence of this synergism, significant improvement in the catalytic performance for the synthesis of $$\upgamma $$ -valerolactone from levulinic acid and formic acid in presence of water has been achieved. The presence of water plays a crucial role in obtaining a higher yield of $$\upgamma $$ -valerolactone. This makes the catalytic system a viable methodology for hydrogenation of levulinic acid to get $$\upgamma $$ -valerolactone. SYNOPSIS: Cu (10wt%) deposited on mesoporous $$\hbox {Fe}_{2}\hbox {O}_{3}$$ prepared by hard template method exhibits good activity in the hydrogenation hydrogenation of levulunic acid with formic acid as $$\hbox {H}_{2}$$ source in vapour phase conditions.