Comparative study of conventional and microwave-assisted pyrolysis, steam and dry reforming of glycerol for syngas production, using a carbonaceous catalyst

The thermal valorization of glycerol to produce synthesis gas has been investigated under conventional and microwave heating systems. Different processes (pyrolysis, steam reforming and dry reforming) are compared, using a commercial activated carbon as catalyst. The reforming processes that employ oxidizing agents (CO2 or H2O) were found to promote higher glycerol conversions than mere thermal decomposition. Steam reforming generates the lowest gas fraction and the highest amounts of hydrogen and syngas, while the opposite occurs in the dry reforming experiments. Microwave processing produced higher gas yields with large syngas content than conventional heating processes in all cases. The use of carbon-based catalysts appears to be highly suitable for producing synthesis gas with a H2/CO ratio close to 1, minimum CO2 emissions being an additional advantage.