A preconcentration procedure for copper, nickel and chromium ions in some food and environmental samples on modified Diaion SP-850

A sensitive and simple method for the simultaneous preconcentration of trace amount of Cu2+, Ni2+ and Cr3+ ions in some real samples has been reported. In this method these elements are adsorbed as respective complex with Bis(2-hydroxyacetophenone)-1,2-propanediimine (BHAPPDI) on Diaion SP-850 and the retained metal ions are eluted using 8 ml of 4 M nitric acid. The influences of the analytical parameters including pH, solid phase ingredients amount and condition of eluting solution and sample volume were investigated. The effects of matrix ions on retentions of the analytes were also examined. The recoveries of analytes were generally higher than 90% with a relatively low RSD. The method has been successfully applied for these metal ions contents evaluation in some food and environmental samples.