The electrocatalytic hydrogenation of furanic compounds in a continuous electrocatalytic membrane reactor

• Published in: Green chemistry : an international journal and green chemistry resource : GC Vol. 15; no. 7; pp. 1869 - 1879
• Main Authors: GREEN, Sara K, LEE, Jechan, HYUNG JU KIM, TOMPSETT, Geoffrey A, WON BAE KIM, HUBER, George W
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.01.2013
• Subjects: Applied sciences; Catalysts; Cathodes; Chemical engineering; Chemistry; Electrochemistry; Exact sciences and technology; Furfural; General and physical chemistry; Hydrogenation; Kinetics and mechanism of reactions; Membranes; Palladium; Reactors; Selectivity; Ionomer; Furfural; Cathode; Membrane electrode assembly; Furan derivatives; Palladium; Aldehyde; Oxygen heterocycle; Electrochemical reactor; Carbon; Hydrogenation; Supported catalyst; Sulfonate copolymer; Electrocatalysis; Membrane reactor; Tetrafluoroethylene copolymer; Cation exchange membrane; Aqueous solution; Platinoid
• ISSN: 1463-9262; 1463-9270
• DOI: 10.1039/c3gc00090g

The electrocatalytic hydrogenation of biomass derived oxygenates in a continuous electrocatalytic membrane reactor presents a promising method of fuel and chemical production that minimizes usage of solvents and has the potential to be powered using renewable electricity. In this paper we demonstrate the use of a continuous-flow electrocatalytic membrane reactor for the reduction of aqueous solutions of furfural into furfuryl alcohol (FA), tetrahydrofurfuryl alcohol (THFA), 2-methylfuran (MF) and 2-methyltetrahydrofuran (MTHF). Protons needed for hydrogenation were obtained from the electrolysis of water at the anode of the reactor. Pd was identified as the most active monometallic catalyst of 5 different catalysts tested for the hydrogenation of aqueous furfural with hydrogen gas in a high-throughput reactor. Thus Pd/C was tested as a cathode catalyst for the electrocatalytic hydrogenation of furfural. At a power input of 0.1W, Pd/C was 4.4 times more active (per active metal site) as a cathode catalyst in the electrocatalytic hydrogenation of furfural than Pt/C. The main products for the electrocatalytic hydrogenation of furfural were FA (54-100% selectivity) and THFA (0-26% selectivity). MF and MTHF were also detected in selectivities of 8%. Varying the reactor temperature between 30 degree C and 70 degree C had a minimal effect on reaction rate for furfural conversion. Using hydrogen gas at the anode, in place of water electrolysis, produced slightly higher rates of product formation at a lower power input. Sparging hydrogen gas on the cathode had no effect on reaction rate or selectivity, and was used to examine the addition of recycling loops to the continuous electrocatalytic membrane reactor.