Synthesis and Functionalization o f porous nanosilica (SBA-۱۵) for remo val of bichromate from aqueous solut ions

Porous nanosilica presents high superficial areas and large unifo rm pores. T he Stucky group synthe sized the Santa Barbara Amorphous (SBA) materials in ۱۹۹۸ and S BA-۱۵ has been well-known as a typical mate rial in this family. SB A-۱۵ mesoporous silica was prepared by pluron ics P۱۲۳ (PEO۲۰PPO۷ ۰PEO۲۰), a long chain organic structure-directing agent under highly acidic and hydrotherm al conditions. It has h igh surface area (۶۰۰–۱ ۰۰۰ m۲/g), well-defined mesoporous structure and thermal stability (up to ۱۰۰۰K ). The nanosilica wall su rface of SBA-۱۵ can be modified w ith organic groups to ta ilor their properties and achieve specific purposes. Functionalization of these materials can be carried out via grafting method in which hydroxyl groups o f SBA-۱۵ react with an organoalkoxysilane co mpound supporting the active functional group. Furthermore , protonated amino-fun ctionalized mesoporous silicas are ap plied for the adsorptive removal of different pollutants such as chromate, arsenate and etc.Chrom ium compounds are extensively used in el ectroplating, leather industry, corrosion control, oxidation and various other industrial app lications. Many approaches have been practi ced in elim inating heavy metal ions, like chemical precipitation, ion exchange, adsorp tion, etc. Among these techniques, adsorption is a relativ ely easy and efficient w ay to remove hexavalen t chromium from wast e water efflu ents [۱-۳]. In this rese arch SBA-۱ ۵ was first synthesized a nd then fun ctionalized.The synthe sized adsorb ent was use d for remo val of bichromate from a queous solu tions under different experimental c onditions.

کلیدواژه ها:

Porous Nanosilic a (SBA-۱۵) ، Functionalization ، Adso rption ، Bic hromate.