FLAME AAS DETERMINATION OF LEAD IN WATER WITH FLOW-INJECTION PRECONCENTRATION AND SPECIATION USING FUNCTIONALIZED CELLULOSE SORBENT

The on-line solid phase extraction of trace amount of lead in flow-inj ection system with flame AAS detection was investigated using cellulos e sorbents with phosphonic acid and carboxymethyl groups, C-18 sorbent non-modified and modified with Pyrocatechol Violet or 8-quinolinol, c ommercial chelating sorbents Chelex 100 and Spheron Oxin 1000, non-pol ar sorbent Amberlite XAD-2 modified with Pyrocatechol Violet and sever al cation-exchange resins. The best dynamic characteristics of retenti on were observed for functionalized cellulose sorbents. For Cellex P a ssumed as optimum sorbent, elution with a separate fractions of nitric acid and ethanol allows the differentiation between tetraalkyllead an d sum of inorganic lead and organolead species of smaller number of al kyl groups. The detection limit for the determination of inorganic Pb( II) was estimated as 0.17 mu g/l, at preconcentration from 50 ml sampl e at a how rate of 7 ml/min.