An inorganic-organic hybrid material made of a silica-immobilized Schiff base receptor and its preliminary use in heavy metal removal

A novel and excellent host for heavy metals was synthesized by chemical immobilization of a (E)-4-(( pyridin-2-yl-methylene)amino)phenol Schiff base receptor onto silica particles. The new hybrid material (SPSB) was analyzed and evaluated by elemental analysis, FT-IR spectroscopy, solid-state C-13 NMR, scanning electron microscopy, BET surface area and BJH analyses. The surface exhibits good thermal stability determined by thermogravimetry and good chemical stability examined in various acidic and buffer solutions (pH 1-7). The coordination ability of SPSB was found to be most efficient in the pH range 6.5-8 for Hg2+, Cd2+, Pb2+ and Zn2+. Alkali coexisting ions did not interfere with separation and determination. The adsorbent can be regenerated at ease without destruction. Heavy metal removal performance (99 mg g(-1)) was found to be higher compared to previous literature reports.