title: Detection and semiquantitative determination of bismuth(III) in water on immobilized and plasticized polyurethane foams with some chromogenic reagents.
abstract: Polyurethane foams immobilizing 1,2-di-(2-fluorophenyl)-3-mercaptoformazan (F(2)H(2)Dz) and dithizone (H(2)Dz) have been used for the detection of bismuth(III) in water via batch, dynamic and pulsated column modes of extraction. The detection limits of bismuth(III) with the F(2)H(2)Dz- and H(2)Dz-immobilized foams were found to be 0.01 and 0.02 mug ml(-1) respectively. Lower concentrations (</=1 ppb) of bismuth(III) were also detected by employing dynamic and pulsated columns packed with plasticized tri-n-butylphosphate and F(2)H(2)Dz-immobilized reagent foams. The electronic spectra and partition coefficients of the reagents H(2)Dz and F(2)H(2)Dz and their bismuth(III) chelates in chloroform and in polyurethane foams have been determined. Bismuth (V) was also detected by the proposed procedure after prior reduction to bismuth(III) with sulphur dioxide at pH < 1. The effect of diverse ions on the detection of 1 mug of bismuth(III) was critically investigated using F(2)H(2)Dz-immobilized foam.
authors.affiliation: Department of Chemistry, Faculty of Science, UAE University, P.O. Box 17551, Al-Ain, United Arab Emirates.
authors.forename: M S
authors.initials: MS
authors.lastname: El-Shahawi
authors.forename: R S
authors.initials: RS
authors.lastname: Al-Mehrezi