Impact of H_(2)S on Hg^(0)capture performance over nitrogen-doped carbon microsphere sorbent:experimental and theoretical insights  

作　　者：Guopei Zhang Xiaoyang Zhang Xiangwen Xing Xiangru Kong Lin Cui Dong Yong 

机构地区：[1]National Engineering Laboratory for Reducing Emissions from Coal Combustion,Shandong University,Jinan,250061,China [2]Bingtuan Energy Development Institute,Shihezi University,Shihezi,832000,China

出　　处：《Frontiers of Chemical Science and Engineering》2024年第3期89-100,共12页化学科学与工程前沿（英文版）

基　　金：supported by National Natural Science Foundation of China(Grant Nos.51976108 and U1906232);Shihezi University Self Funded Support Project(ZZZC2023069).

摘　　要：A nitrogen-doped carbon microsphere sorbent with a hierarchical porous structure was synthesized via aggregation-hydrothermal carbonization.The Hg^(0)adsorption performance of the nitrogen-doped carbon microsphere sorbent was tested and compared with that of the coconut shell activated carbon prepared in the laboratory.The effect of H_(2)S on Hg^(0)adsorption was also investigated.The nitrogen-doped carbon microsphere sorbent exhibited superior mercury removal performance compared with that of coconut shell activated carbon.In the absence of H_(2)S at a low temperature(≤100℃),the Hg^(0)removal efficiency of the nitrogen-doped carbon microsphere sorbent exceeded 90%.This value is significantly higher than that of coconut shell activated carbon,which is approximately 45%.H_(2)S significantly enhanced the Hg^(0)removal performance of the nitrogen-doped carbon microsphere sorbent at higher temperatures(100–180℃).The hierarchical porous structure facilitated the diffusion and adsorption of H_(2)S and Hg^(0),while the nitrogen-containing active sites significantly improved the adsorption and dissociation capabilities of H_(2)S,contributing to the generation of more active sulfur species on the surface of the nitrogen-doped carbon microsphere sorbent.The formation of active sulfur species and HgS on the sorbent surface was further confirmed using X-ray photoelectron spectroscopy and Hg^(0)temperature-programmed desorption tests.Density functional theory was employed to elucidate the adsorption and transformation of Hg^(0)on the sorbent surface.H_(2)S adsorbed and dissociated on the sorbent surface,generating active sulfur species that reacted with gaseous Hg^(0)to form HgS.

关 键 词：nitrogen-doped carbon microsphere H_(2)S Hg^(0)removal adsorption mechanism 

分 类 号：O64[理学—物理化学]