Synthesis Of Functionalized Mesoporous Materials And Their Adsorption Behavior For Heavy Metal Ions

In present, heavy metal pollution has become increasingly serious and harm to humanlife and the natural environment. Heavy metals have higher mobility and cause poisoning by alow concentration. It’s enriched through organisms from the food chain in huaman body.The adsorption method is a common way to deal with heavy metal ions and requires theadsorbent have high adsorb capacity and excellent reuse performance. The mesoporousmaterial is widely used in adsorption, optical materials, catalyst because of the highly orderedpore structure, large specific surface area and stable chemical properties. But mesoporoussilicas’ application is limited as the result of the single chemical activity. The functionalizedmesoporous for special application can be made by introducing the specific organic group. Inthis paper, a number of mesoporous materials were synthesized by introducing some specificorganic group which could chelate with heavy metals. The main work was summarized asfollows:Firstly,three kind of bridged silane were synthesized: γ-Mercaptopropyltriethoxysilane bonded with1,4-dibromobenzene,3-（triethoxysilyl）-propyisocyanate bondedwith1,4-benzenedithiol and diamino diphenyl sulfone. Under the acid condition,three seriesof bridged functioned mesoporous organosilicas were prepared by the co-condensationbetween the obtained bridged silane and TEOS via the template CTAB. The structuralcharacterization result showed that the materials have large pore volume and large specificsurface area. The pore size becomes gradually smaller when the content of organic groupincreases.Secondly, the adsorption of heavy metal were studied with the three series of PMOsmaterials. The result showed: all the materials have high adsorb capacity and selectiveadsorption of Hg²⁺. The cycling performance is excellent. The adsorption of Hg²⁺is shown tobe monolayer adsorption through Langmuir equation.