SYNTHESIS AND CHARACTERIZATION OF ORDERED MESOPOROUS MATERIALS FOR REMOVAL OF HEAVY METAL IONS

摘要

Synthesis and characterization of novel multifunctional adsorbents for mercury ions from aqueous solutions, based on ordered mesoporous materials (OMMs), is reviewed. Ordered mesoporous silicas (OMSs) with chemically bonded surface ligands and periodic mesoporous organosilicas (PMOs) with incorporated bridging groups are compared with respect to their adsorption properties and affinity towards heavy metal ions. Various types of OMSs possessing a hexagonal or cubic arrangement of ordered mesopores, grafted with multifunctional 1-benzoyl-3-propylthiourea and 2,5-dimercapto-1,3,4-thiadiazole ligands, are compared to PMOs containing specific bridging groups incorporated directly into the silica framework. PMOs having a single type of organic functionality (e.g., tris[3-(trimethoxysilyl)propyl]isocyanurate) in the framework, or multiple framework and surface functionality (e.g., tris[3-(trimethoxysilyl) propyl]isocyanurate and 3-mercaptopropyl, respectively) are discussed. Nitrogen adsorption was a main method used to monitor changes in the porous structures of OMMs upon surface and framework modification.