Abstract:Biomass pyrolysis for high-valued products is an important development direction for biomass utilization. Biomass contains large amounts of O-containing groups. If using nitrogen to substitute oxygen, we may obtain abundant N-doped carbon materials contain lots of active N-containing groups, which can be applied in catalysis, adsorption, and energy storage. This research focused on formation mechanisms of N-doped carbon during introducing exogenous nitrogen, which is in favor of realizing efficient and valuable utilization of biomass wastes. The main works are shown as follows: NH3 was used as exogenous nitrogen to investigate the regulation evolution of N-containing species from bamboo wastes N-enriched pyrolysis at different temperature and NH3 concentration. Formation mechanism of N-doped carbon was revealed. O-containing groups in char reacted with NH3, NH2* and NH*, and formed large quantities of N-containing groups through Maillard reactions. To improve the quality of N-doped carbon materials, KOH activator was introduced in N-enriched pyrolysis to investigate the synergistic effect of NH3 and KOH on N-doped carbon materials. KOH reacted with active functional groups in biomass, and removed large amounts of O-containing groups to generate abundant active vacancies.
