Catalytic pyrolysis of pine needle biomass over Fe–Co–K catalyst for H2-rich syngas production: Influence of catalyst preparation

In this work, the effects of preparation methods of Fe–Co–K catalysts on biomass pyrolysis were studied in a fixed bed reactor under 0.1 MPa N2 and 700 °C. The results showed that Fe–Co bimetallic catalyst has better activity than Fe. the yields of H2 and CO increased from 84.90 ml/g and 63.94 ml/g (Fe) to 98.42 ml/g and 85.43 ml/g (Fe + Co) prepared by co-impregnation, respectively, and the CO2 yield was 276.94 ml/g. The preparation of Fe∗ + Co∗ catalyst by co-precipitation could not only improve the yields of H2 (138.23 ml/g) and CO (89.75 ml/g), but also reduce the CO2 yield (225.19 ml/g). In the Fe∗ + Co∗ catalyst system, the addition of 0.6 wt% K increased the yields of H2 and CO to 153.85 ml/g and 107.80 ml/g. Characterization proved that the crystallinity of Co3Fe7 in Fe∗+Co∗ was stronger than that of Fe + Co, and the addition of Co facilitates the reduction of Fe, K promoted the dispersion of Fe∗ + Co∗ and enhanced the catalytic activity. This study provided theoretical support for increasing the yields of H2 and CO while reducing the CO2 yield.