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本研究采用密度泛函理论（DFT）研究了在γ-Fe2O3表面HCl对Hg0的吸附和催化氧化的作用机制。构建了Hg0、HCl、HgCl和HgCl2在γ-Fe2O3(001)表面的吸附模型，分析了HCl对γ-Fe2O3表面催化氧化Hg0的作用机理，并通过反应路径的能量分布测定，研究了γ-Fe2O3表面Hg0的氧化过程。结果表明，Hg0倾向于化学吸附在γ-Fe2O3(001)表面Feoct位。HCl在催化剂表面进行解离吸附，形成吸附态Cl和羟基，从而促进Hg0的吸附。HgCl以分子形式化学吸附在γ-Fe2O3(001)上，并作为Hg0氧化过程的中间体。HgCl2倾向在γ-Fe2O3表面上的平行吸附。同时，HCl在γ-Fe2O3(001)上氧化Hg0遵循L-H机理，即化学吸附的Hg0与解离吸附的HCl反应，且HCl对Hg0的非均相氧化通过两步反应途径进行，即Hg0 (ads)→HgCl(ads)→HgCl2(ads)。

A molecular modeling based on the density functional theory (DFT) and the transition state theory (TST) was performed to investigate the influence of biomass gas CO on the N2O decomposition catalyzed by CaO during reburning in the circulating fluidized bed boiler. The model for N2O adsorption onto the CaO(100) surfaces were constructed; and the processes of the N2O decomposition on the CaO(100) surface and the surface recovery of CaO(100) were investigated. The results illustrate that the energy barrier of N2O decomposition on the CaO(100) surface is much lower than that in homogeneous case, and CaO is therefore able to catalyze the N2O decomposition. The atomic O from N2O decomposition can poison the active sites O atom on the CaO(100) surface, while biomass gas CO can promote the regeneration of the active sites on the surface of CaO(100), which is beneficial for CaO to catalyze the N2O removal.