Electrocatalytic Selective Oxidation of Glycerol to Tartronate and Electricity Generation Using Au, Pd Mono and Bimetallic Nanoparticles Supported On Carbon Nanotube As Anode Catalyst in Anion Exchange Membrane Fuel Cell

Electrocatalytic selective oxidation of glycerol to tartronate with electricity generation using Au, Pd mono and bimetallic nanoparticles supported on carbon nanotube as anode catalyst in anion exchange membrane fuel cell

Ji Qi¹, Le Xin¹, David Chadderdon¹, Yang Qiu¹, Yibo Jiang², Zhiyong Zhang¹, Wenzhen Li¹

 

¹Department of Chemical Engineering, Michigan Technological University

²Department of Civil & Environmental Engineering, Michigan Technological University

As a renewable biomass feedstock, glycerol can be valorized to a series of chemical products, among which tartronic acid is one of the most expensive chemicals. Since glycerol oxidation reaction (GOR) is spontaneous reaction with negative Gibbs free energy change, it's suitable to investigate GOR in fuel cell to simultaneously obtain high yield of value-added product and high electricity output. Studying the GOR in fuel cell not only have profitable application value, but also provides deep scientific insights into the difference between electrocatalytic reaction process and heterogeneous catalytic reaction process.

In the present work, Au, Pd mono and bimetallic nanoparticles supported on carbon nanotube (CNT) were prepared and used for glycerol oxidation in anion exchange membrane fuel cell. In the past, fuel cell anode potential window is very narrow. Therefore, high selectivity of tartronate can only be obtained by consuming electricity in electrolysis cell which has a relatively large anode potential window. We successfully designed the electrode structure of fuel cell to lower down the anode potential in the fuel cell and thus prevent overoxidation of tartronate to mesoxalate and C-C bond cleavage. Also, the reaction rate is increased by alloying PdAu, leading to high instantaneous electricity output. During the 8 h reaction process, stable 50 mW cm^-2 to 5 mW cm^-2 can be generated with 67% yield of tartronate finally achieved using PdAu alloyed nanoparticles supported on CNT as anode catalyst. Future work includes optimizing the catalyst synthesis method and other operating parameters to further increase yield of different kinds of target products.