Producing Hydrogen-rich Gas by Fresh Biomass Co-pyrolysis with Additive

Abstract

Pyrolysis properties of fresh ficus lacor leaves with moisture content of 70wt. % was investigated in a TGA setup. The effects of different operating parameters on pyrolysis of biomass were studied in a fixed-bed reactor system. With addition of CaO, there showed an additional decrease in weight at temperature range of 382~490 °C, but 12wt. % weight was recovered in the first stage (40~220 °C). Fresh biomass pyrolysis was calculated to be first order reaction with activation energy about 29.8 kJ mol -1 . Activation energy was lowered to 20.4 kJ mol -1 by addition of CaO. With scope of temperature studied, higher temperature was found always favor hydrogen production during pyrolysis of fresh biomass. Carbonation and hydration of CaO enhanced water gas shift reaction (WGS) which led to hydrogen yield increasing. The highest hydrogen content (around 70vol. %) of hydrogen concentration and hydrogen yield (23.2 ml g -1 -biomass) were achieved when CaO/biomass mass ratio increased to 0.3. Pyrolysis of fresh biomass without pre-drying showed the potential of hydrogen production.