Chemical looping gasification of pyrolyzed biomass and coal char with copper ferrite as an oxygen carrier

Chemical looping gasification (CLG) of solid fuels (biomass or coal) is an effective gasification technology. In this work, CuFe2O4 spinel was used as an oxygen carrier (OC) in CLG. Coal and biomass char heat-treated at 600 °C, 700 °C, and 800 °C were used as fuels. The reactivity of char heat-treated at 600 °C and OC was studied using thermogravimetry. The results showed that the optimal mass ratio of OC/char is 6:4. Under this condition, the highest reactivity of char heat-treated at 600 °C was obtained. The gas composition was tested in a fixed bed at various OC/char mass ratios (7:3, 6:4, 5:5, 4:6, and 3:7). The CO yield increases with the decrease in the oxygen carrier ratio. An opposite trend was observed in the CO2 yield. In addition, six kinetic models were used to study the mechanism of CLG. The modified random pore model is found to be optimum in describing experimental data. The results showed that the OC/char in CLG is influenced by pores and catalytic active sites.