A novel catalyst-free process for producing hydrogen and carboxylate from biomass-derived alcohols

•Carboxylates and H2 were produced under mild conditions without using any catalyst.•The purity of hydrogen was up to 99.8%.•No CO or CO2 was detected in the gas products.•The mechanism was proposed and verified.

In this study, we presented an unexpected environmentally benign and easy-to-implement reaction for producing highly pure hydrogen (99.8%) and value-added carboxylate from primary alcohols under basic conditions. No catalyst was required, and no environmentally harmful gas, such as CO and CO2, was produced. The reaction conditions, different reactants and the water tolerance of the reaction were examined. It was found that as long as the temperature is higher than 500 K, no matter what the pressure is, hydrogen and carboxylate can be produced from primary alcohols. Strong alkalinity and high solubility of the base is necessary for the reaction. It was confirmed that ethanol-water mixtures, which could be produced from biomass fermentation, can be used as feedstock in this process, making it more meaningful in terms of sustainability. The mechanism of the reaction was also investigated in detail.