Alcohols and polyols can be produced from biomass (and are a by-product of biofuel industry in the case of glycerol) and represent an interesting challenge for the production of platform molecules for further chemical transformations into polymers, surfactants, etc. The main challenges are then reaching a high activity and controlling the selectivity of the anode. These challenges can be addressed by the reaction medium and the catalyst design with modification of catalytic metals (generally platinum group metal) with p-group and d-group metals to improve the activity and tune the selectivity towards desired reaction products [1,4-7].
The use of saccharide for hydrogen and value-added chemical cogeneration would represent a convenient way of introducing biosourced molecules in the hydrogen and platform molecules production chain. Indeed, a large part of cellulosic biomass which is not devoted to food industry is composed of saccharide derivatives. The production of saccharide from these resources is then less demanding in terms of energy and chemical steps than alcohol / polyol production. Furthermore, the oxidation of saccharide in alkaline medium under conditions similar to that of an electro-reforming cell [8] leads to the formation of carboxylic acids very similar to those produced from alcohol / polyol electro-reforming and to longer carboxylic acids. However, while the oxidation of saccharide such as glucose and xylose starts at low potential, it remains difficult to reach high current densities compatible with an industrial process and the reactant turnover has to be improved.
Finally, the conversion of these compounds is performed with co-production of clean hydrogen on the cathode, at low cell voltage (typically less than 1 V) compared to water electrolysis [2–4,7].
Acknowledgement: The research leading to these results has received funding from the French National Research Agency (ANR) under grant agreement N° ANR-16-CE29-0007-01 (ECO-PLAN project)
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