8-Hydroxyquinoline grafted nanoporous SBA-15 as a novel solid phase extractor for preconcentration of trace amount of Copper

In this study, the potential of 8-Hydroxyquinoline grafted SBA-15 to extract of Cu2+ cations from aqueous solutions was investigated. SBA-15 nanoporous silica was chemically grafted with 8-Hydroxyquinoline groupsaccording to the procedure in the literature. The presence of organic groups in the silica framework was demonstrated by FTIR spectrum. The grafted product showed the BET surface area 458 m2g-1 and pore diameter 54 ºA, based on adsorption-desorption of N2 at 77 ºK.. Flame atomic absorption spectrometry was used to determination of the ions concentration in the recovery and sample solution. The effects of several variables (amount of adsorbent, stirring time, pH and the presence of other metals in the medium) were studied. Cu2+ ions were completely extracted at pH= 4.5-7 after stirring for 15 minutes. The maximum capacity of the adsorbent was found to be 31.25 mg of Cu2+ per each gram of 8-Hydroxyquinoline grafted SBA-15. The minimum amount of acid for stripping of ions from grafted SBA-15 was tested and the preconcentration factor of the method was found 50. Finally, the proposed method was successfully applied as a new solid extractor to preconcentration and determination of trace amounts of Cu2+ ions in spiked distilled and tap water samples.