Multiple techniques have been developed during the past decades to convert bioethanol to hydrogen by following the reaction (1).

C2HsOH(l) + 3 H2O(l) 2 CO2 + 6 H2 (AHr,298K = 348 kJ/mol)

It is clearly observed that 6 moles of hydrogen can be produced per mole of ethanol fed. However, the highly endothermic feature of this reaction requires external energy supply. Depending on the type of energy input, the current hydrogen production technologies can be categorized into two areas: non-thermal including bio, photo, plasma, and thermal — chemical processes. Besides, several hybrid systems have also been recently developed to produce hydrogen relying on the energy supply of more than one source (e. g., photo­fermentation and thermal plasma). Compared to thermochemical conversion, non-thermal hydrogen production can take place at much mild conditions with minimal thermo-energy input requirement from surroundings. However, the biological or photo hydrogen production efficiency is much lower than acceptable scale for industrial application. Unlike biological or photo process, thermochemical conversion can happen at much higher reaction rate, but under relatively severe conditions (e. g., high temperature and pressure) with notable amount of thermo-energy input. In addition to water, CO2 (dry reforming) and O2 (partial oxidation or oxidative reforming) can also act as oxidant to oxidize ethanol for hydrogen production. Among all the available techniques described in details in this section, steam reforming might possess the highest potential to be commercialized in the near term.