SELECTIVE ADSORPTION OF HEAVY METAL IONS USING MOLECULAR-IMPRINTED ADSORBENTS SYNTHESIZED WITH LOW COST SILICA SOURCES

摘要

PURPOSE: A method for preparing a mesoporous-silica that is bound with chelating-ligand for selective adsorption of heavy metal ions in wastewater is provided. CONSTITUTION: The preparation method of the mesoporous-silica includes the steps of reaction of silica precursor selected from sodium silicate or sodium metasilicate with structure derivative selected from Triton X-100, Tergitol 15S12, Pluronic P123, neutral-surfactant of amine series and polyethylene-polypropylene block copolymer; hydrolysis and condensation of silica precursor in the presence of hydrochloric acid as catalyst; drying at ambient temperature and then drying again at 50-150deg.C; removal of residual surfactant by soxhlet extraction using ethanol, followed by drying; forming chemical bond of a template obtained in above step with chelating ligand that is bound with heavy metal ions, wherein the chelating ligand that is bound with heavy metal ions is selected from aminopropylethoxysilane, aminoethyl aminopropyl methoxysilane, trimethoxysilyl propyl diethylenetriamine, trimethoxysilylpropyl ethylenediaminetriacetate sodium salt and its mixture; elimination of residual chelating ligand and heavy metal ions by using alcohol and acid solution; and drying at ambient temperature for 10-48 hours and then drying again at 50-150deg.C for about 1 hours.