Electrocatalytic Hydrogenation of Furfural using Bimetallic Catalysts based on Pd, Ni and Cu

Abstract

The electrocatalytic hydrogenation of biomass-derived compounds using a continuous electrocatalytic reactor is a promising technique for fuel and high-value chemicals production. However, understanding the impact of different types of active electrodes used and various recation conditions on electrocatalytic biomass oxygenates conversion and products selectivity limits the process of industrialization. In this study, a hydrogen-cell system has been utilized for the conversion of furfural (FF) under ambient conditions. Different nickel-based and copper-based alloy catalysts were synthesized following a cost-effective method. Insights about the structure, morphology, purity, crystallinity as well as the chemical composition of synthesized nanoparticles were gained and compared using X-ray Diffraction (XRD), Scanning electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and transmission electron microscopy (TEM). Initially, the electrochemical behavior of the prepared electrodes was captured via conducting several electrochemical studies, such as Electrochemical Impedance Spectroscopy (EIS), Linear Sweep Voltammetry (LSV), and Cyclic Voltammetry (CV). A significant increase in current density was observed after the addition of furfural when using nickel alloys, thus indicating higher activity towards furfural conversion. Additionally, the catalytic performance of nickel-alloys and copper alloys was determined by comparing the percentage conversion of furfural as well as the product's selectivity. Moreover, the impact of various reaction parameters was investigated such as electrolyte pH, initial furfural (FF) concentration, and applied potential utilizing both electrochemical and conversion experiemts. The novelty of this work arises from the use of various affordable, alloyed, heterogeneous catalysts with different nickel to palladium molar ratios, which has resulted in supriuor catalytic activity for furfural conversion of over 65% after only 4.5 hours of reactions. Additionally, exceptional catalytic performance with high selectivity towards 2- metylfuran production of 23.4% after 2.3 hours of reaction was observed for electrode Ni0.85 Pd0.15. Moreover, high selectivity towards furfuryl alcohol production (51.7%) was achieved after 1.5 hours using Cu0.85Pd0.15 electrode. Obtained promising results suggest the effectiveness of alloying a commonly used catalyst such as nickel or copper with a small fraction of a noble metal on boosting the electrocatalytic activity. Additionally, the use of affordable heterogenous alloyed catalysts suggests the effectiveness of the designed electrocatalytic system for industrialization.

Date of Award	May 2022
Original language	American English