Fast Monitoring of the Phosphate Ions at Sub-mg L level with the Aim of Diamine-grafted MCM-41 Mesoporous silica and Ion Chromatography

Subject Areas : Polymer

Leila Hajiaghababaei ¹ , Sima Djam ²

1 -
2 -

Received: 2015-12-28 Accepted : 2015-12-28 Published : 2015-10-01

Keywords:

Abstract :

In this work, an innovative method is described for the preconcentration of phosphate ions using ethylenediamine functionalized mesopor (MCM-41). Functionalized MCM-41 was synthesized and the presence of organic groups in the silica framework was demonstrated by FTIR spectrum. The amount of organic groups immobilized on silica surface was determined by elemental analysis and TGA. The functionalized product showed the BET surface area 804 m2g-1, BJH pore diameter 3.28 nm and pore volume 0.27 cm3g-1, based on adsorption- desorption of N2at 77 K. The phosphate ions were identified by ion chromatography (IC). The enrichment factor of the proposed method was 100 and detection limit was found to be 0.3μg L-1 . The time of extraction, pH, the optimum amount of the sorbent and amount of sodium hydroxide solution for stripping were investigated. The maximum capacity the adsorbent was found to be 12.0 (±1.4) μg phosphate/mg diamine-grafted MCM-41. The method was applied successfully for the determination of trace amounts of phosphate ions in water samples.