USE OF THE COMPOSITE CELLULOSE-ZIRCONIUM(IV) OXIDE IN A CHROMIUM(VI) PRECONCENTRATION IN-LINE IN A FLOW-INJECTION ANALYSIS SYSTEM

Determination of Cr(VI) using the composite cellulose-zirconium(IV) oxide with 5% w/w of zirconium was possible, A flow injection system in line with a minicolumn with the material was used to selectively adsorb Cr(VI). By injecting a standard solution of Cr(VI) 50 mu g dm(-3), pH 1, at different loading times (10, 40, 70 and 100 seconds), a linear correlation between absorbance and mass of Cr(VI) was obtained, Samples with Cr(VI) between 2 and 50 mu g dm(-3) were analyzed. The relative standard deviations were found within 1.87 and 6.88%. Analysis of Cr(VI) in presence of interferent ions, Cr(III), Cu(II), Mn(II), Hg(II), Fe(III), VO3-, MoO42-, SO42-, PO43- and MnO4-, were also studied.