CO2 pyrolysis kinetics and characteristics of lignin-rich hydrolysis residue produced from a tandem process of steam-stripping and acid hydrolysis

•CO2 pyrolysis characteristics and kinetics of lignin-rich hydrolysis residue were investigated.•Real kinetic parameters was evaluated using two types of distributed activation energy model.•A middle difference method with variable step for calculating differential term was developed.•The effective range of mean activation energy ranges from 261.26 kJ mol−1 to 271.36 kJ mol−1.•The kinetic model with distributed-fitting method could predict the pyrolysis process well.