Catalytic cracking of biomass tar using Ni nanoparticles embedded carbon nanofiber/porous carbon catalysts

The major obstacles for catalytic cracking of biomass tar have been known as the low tar removal efficiency and catalyst deactivation . In view of this, the novel Ni nanoparticles embedded carbon nanofiber/porous carbon catalysts were synthesized by the method of hydrothermal treatment combined with carbothermal reduction . The properties of catalysts were evaluated by characterization of N 2 adsorption-desorption, SEM , XRD , TEM, H 2 -TPRand Raman, meanwhile the evolutionary mechanism of catalysts was also proposed. The tar catalytic cracking tests indicated that the Ni 0.30 @CF/PCs exhibited the favorable catalytic activity with the high tar conversion efficiency (94.78%) as well as the better catalytic stability at the catalytic cracking temperature of 700 °C compared to other catalysts. In the case of Ni 0.30 @CF/PCs, the carbon nanofiber/porous carbon composites with hierarchical micro-mesoporous structure and high graphitization degree as well as the Ni nanoparticles embedded in catalyst support with the strong metal-support interaction exhibited the favorable activity-structure relationship. In addition, the Ni 0.30 @CF/PCs catalyst also presented the high tar conversion efficiency of 93.31% after 10 cycles, which was due to the high resistance towards coke deposition and sintering of metallic Ni covered by graphite layer from the carbothermal reduction process.