One-pot catalytic conversion of cellulose to ethanol at low pressure and temperature conditions: H2O as self hydrolytic and hydrogenating agent

Abstract

In this research article, ethanol production has been proposed through the one-pot catalytic conversion of microcrystalline cellulose (MCC) over Pd-Ni/iron catalysts without any prior reduction under viable and inert experimental conditions. The Pd-Ni on iron oxide catalysts was prepared by facile co-precipitation and impregnation methods. Under optimized experimental conditions, the synthesized catalysts were systematically tested for efficient conversion of microcrystalline cellulose using H2O as a green solvent, hydrolytic and self-protonating agent. The different ethanol yields and microcrystalline cellulose conversions obtained over impregnated and co-precipitated catalysts were obtained under different temperatures and pressure conditions, respectively. However, the catalyst used in the impregnation method afforded higher ethanol yields than co-precipitated catalysts under similar conditions. The impregnated Pd-Ni/iron oxide catalyst provided improved catalytic activity due to uniformly dispersed active metal particles, optimum crystalline size and structure, and high surface area. The characterization of the catalysts was carried out by XRD, BET, and FTIR techniques. From FTIR and XRD analyses, it was clearly observed that the Pd-Ni/iron oxide catalyst forms Fe-O, Pd-O, NiFe2O4 and Ni-O functional groups. In addition, the spent catalyst was tested for reusability to determine its reactivity towards cellulose conversion. The results show that the spent catalyst could convert maximum amounts of microcrystalline cellulose and achieved comparable yields to fresh catalyst.