Supercritical water gasification for hydrogen production

The production of energy in the form of hydrogen through industrial, rural and urban waste is a sustainable technology concept, since this waste does not add economic value and is considered an environmental obstacle. The use of hydrogen as an energy vector, produced from residual biomass, can be evaluated as an interesting form of energy storage. Hydrogen can be produced by gasifying biomass with a high water content. Supercritical water (Tc = 374 °C, Pc = 221 bar) has unique physicochemical properties that minimize mass transport limitations, making it an excellent medium for decomposing organic compounds. In view of this, it is extremely important to know the key factors necessary for the efficient application of biomass gasification in supercritical water. Therefore, this review aims to gather information on the main factors involved in these reactions. In addition, some of the operational challenges and the state of the art regarding the main biomass models have been raised.