Pyrolysis and subsequent steam gasification of metal dry impregnated lignin for the production of H2-rich syngas and magnetic activated carbon
Tong Han, Weihong Yang, Pär G. Jönsson
Abstract
An integrated process that includes the pyrolysis of FeSO4 dry impregnated lignin and subsequent steam gasification of the produced biochar has been performed to produce H2-rich syngas and magnetic activated carbon. The results show that gasification is more beneficial for hydrogen production than pyrolysis. Increasing the pyrolysis temperature from 550 °C to 800 °C and iron loading from 4% to 8% not only promotes the extension decomposition of lignin but also induces the production of char, which is more effective for gasification. As a result, the syngas yield and H2 volumetric percentage of both the pyrolysis and steam gasification processes are enhanced. The maximum overall H2 yield and exergy efficiency for producing H2 are estimated to be 42.73 mol/kg-lignin and 46.63%, respectively. Magnetic activated carbon materials produced from the proposed integrated process have a good porous property and high saturation magnetization value. Magnetic activated carbon that is produced from the same process that achieves a maximum H2 yield is obtained and exhibits an approximate 70% total phosphate and 20% ammonia and nitrogen removal efficiency for treating real domestic wastewater.