摘要
研究了胺基表面官能化前后的HMS(hexagonal mesoporous silica)对腐殖酸的吸附,Freundlich方程拟合结果表明,表面官能化后吸附常数K值由0.56提高至105,反映出表面官能化能显著改善HMS对腐殖酸的吸附,且低pH值条件下吸附效果更佳.表征结果显示,腐殖酸分子主要吸附在表面胺化HMS的中孔孔道内,并首先占据吸附剂中较大的中孔孔道.吸附动力学结果显示腐殖酸在表面胺化的HMS上吸附符合二级动力学,吸附速率主要受孔道内扩散控制.
The adsorption of humic acid onto hexagonal mesoporous silica（HMS） and surface aminated HMS was investigated. The simulation results using Freundlich model indicated that the surface amination of HMS led to an increase of adsorption constant from 0.56 to 105, reflecting markedly enhanced adsorption of humic acid upon surface amination. In addition, humic acid adsorption under acidic conditions was favored. Adsorbed humic acid molecules were found to be located in the mesopores of aminated HMS and the mesopores with relatively larger pore diameters were preferentially occupied. The kinetics of humic acid adsorption onto the aminated HMS could be well described by second order kinetics and the adsorption rate was mainly dominated by intrapore diffusion process.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2008年第5期1197-1202,共6页
Environmental Science
基金
国家自然科学基金项目(40402022,20637030)
江苏省环境工程重点实验室开放课题项目(KF2007002)
关键词
胺基官能化
HMS
腐殖酸
吸附
amino functionalization
hexagonal mesoporous silica（ HMS）
humic acid
adsorption
