Trace Analysis by Direct Spectrophotometric Measurements on Polyurethane Foam. Determination of Chromium (VI) as Blue Perchromic Acid with Unloaded & Tri-n-Butylphosphate Loaded Foam

Abstract The formation of blue perchromic acid represents one of the most sensitive and selective tests for the identification of chromium. The sorption of perchromic acid on TBP loaded foam has been investigated for the detection, semiquantitative and quantitative determinations of chromium (VI). In foam batch method, it was possible to detect as los as 0.6, 0.4 and 0.2 ppm of chromium (VI) with unloaded or tricaprylylamine loaded foams, TBP-amine-loaded foams and TBP loaded foams, respectively.