摘要
基于密度泛函理论,采用Materials Studio软件建立稻壳焦和CuCl2改性稻壳焦模型,对汞吸附前后模型进行计算分析,旨在从微观角度分析稻壳焦脱汞机理.结果表明:在吸附过程中,Hg原子上的电子会转移到稻壳焦表面,从而在二者之间形成范德华力,将Hg原子束缚在稻壳焦表面,形成汞的物理吸附;而CuCl2改性稻壳焦在吸附汞时,表面CuCl2分子中的Cu-Cl键会发生断裂,断裂后Cu和C1会与Hg原子结合,形成汞的化学吸附,使得CuCl2改性稻壳焦的脱汞效率远高于原始稻壳焦,明确了 CuCl2改性稻壳焦脱汞机理,对生物质焦吸附剂脱汞的工业应用具有理论指导.
Abstract
Based on density functional theory,models of rice husk char and CuCl2-modified rice husk char were established using Materials Studio software to calculate and analyze these models before and after mercury adsorption.The mechanism of mercury removal by rice husk char was analyzed from a microscopic perspective.Results show that during the adsorption process,electrons on Hg atoms are transferred to the surface of rice husk char.Van der Waals forces are formed between them,and Hg atoms are binded to the surface of rice husk char in the form of physical adsorption.While CuCl2-modified rice husk char can break one of Cu-Cl bonds in CuCl2 on the surface of char in the mercury adsorption process.Cu atom and Cl atom will combine with Hg atom to form mercury chemisorption,which results in higher mercury removal effi-ciency by CuCl2-modified rice husk char than that of original rice husk char.It can provide theoretical guid-ance for the industrial application of biomass char adsorbents to mercury removal by clarifying its corre-sponding mechanism.
基金项目
国家能源集团科技创新资助项目(CF9300220004)
万方数据