Steam reforming of crude glycerol with in situ CO2 sorption

Steam reforming of the crude glycerol by-product of a biodiesel production plant has been evaluated experimentally at atmospheric pressure, with and without in situ CO2 sorption, in a continuous flow fixed-bed reactor between 400 °C and 700 °C. The process outputs were compared to those using pure glycerol. Thermodynamic equilibrium calculations were used to assess the effect on the steam reforming process of the main crude impurities (methanol and four fatty acid methyl esters). The crude glycerol and steam conversions and the H2 purity reached 100%, 11% and 68%, respectively at 600 °C. No CH4 was found at and above 600 °C. Steam reforming of crude glycerol with in situ CO2 removal is shown to be an effective means of achieving hydrogen purity above 88% in pre-CO2 breakthrough conditions.