Microwave pyrolysis of corn stover

This study investigated microwave pyrolysis of corn stover under different conditions. The process yielded bio-oil, gas, and solid charcoal residue. Under experimental conditions, a power input level above 300 W was necessary to initiate thermal pyrolysis of a 50 g sample of corn stover. The yields of gas and bio-oil increased to 46.9 wt % and 30.2 wt %, respectively, when microwave input power increased from 300 to 900 W. A higher power input also favored gas production. Adding 1 wt % pyrolytic charcoal residue to the pyrolysis of corn stover increased the bio-oil and gas yields, particularly the bio-oil yield. Addition of NaOH to the pyrolysis of corn stover as catalyst increased the gas yield greatly. The chemical profiles of the gas and bio-oils were also determined using GC and GC-MS, respectively. This study demonstrated that microwave pyrolysis can be optimized to produce valuable gas and liquid bio-fuel.