Utilization of CO2 and biomass char derived from pyrolysis of Dunaliella salina: The effects of steam and catalyst on CO and H2 gas production

► Highlight renewable use of biomass char derived from pyrolysis of Dunaliella salina. ► The approach mitigated CO2 emission, and produced CO-rich. ► A new approach for improving H2 was carried out by using biomass char and Au/Al2O3. ► We combined steam gasification of char and water gas shift reaction of Au/Al2O3.