生物质热解焦油CO2重整技术研究进展

Pyrolysis technology for gas production in high temperature is an important research direction in the field of biomass resource utilization. However, the application of high temperature pyrolysis technology is limited due to the problems of clogging, corrosion, and difficult utilization of pyrolysis tar. The catalytic CO2 reforming of pyrolysis tar can achieve the synergistic conversion of tar and CO2 into H2and CO, reducing the content of pyrolysis tar and CO2 and improving the energy recovery efficiency of the system. During catalytic CO2 reforming of pyrolysis tar process, noble metal catalysts have high catalytic activity, but the large-scale industrial application of noble metalcatalysts is limited due to the high cost. Among transition metal catalysts, nickel-based catalysts have high catalytic activity and low cost,but the reaction activity will decrease due to the problems such as sintering, agglomeration, and coke deposition of metal nickel particlesat high temperatures, limiting the long-term operation of nickel-based catalysts. Due to the thermodynamic limitation, the active components of nickel-based catalysts are prone to agglomeration and sintering at high temperatures. Focusing on the sintering deactivation ofnickel-based catalysts, the Taman temperature of nickel particle can be increased and the anti-sintering performance of nickel-based catalysts can be improved by doping a small amount of noble metals. On the other hand, constructing a core-shell structure on the surface ofnickel particles can effectively limit the phase migration, agglomeration, and sintering deactivation of active metals by improving the dispersion of nickel metal particles in the shell layer. High temperatures in the catalytic CO2 reforming of tar process can promote reactions,such as tar cracking and CO disproportionation to form coke deposition on catalyst surface. Considering the deactivation of coke depositionon nickel-based catalysts, metal doping modification, core shell structure modification, and air introduction can limit the deposition of filamentous and slow down the deactivation caused by coke deposition.