title: Sensitive detection and semiquantitative determination of mercury(II) and lead(II) in aqueous media using polyurethane foam immobilized 1,5-di-(2-fluorophenyl)-3-mercaptoformazan.
abstract: 1,5-Di-(2-fluorophenyl)-3-mercaptoformazan (F(2)H(2)Dz) immobilized and plasticized with tri-n-butylphosphate (TBP) polyurethane foam (PUF) were found suitable for the detection of mercury(II) and lead(II) in extremely dilute aqueous solutions. In batch mode of extraction with immobilized F(2)H(2)Dz-foam as low as 0.05 and 0.15 mug ml(-1) of mercury(II) and lead(II), respectively were detected and the colored chelates were found more stable over 72 h. Lower concentrations of these metal ions (</=1 ppb) were detected by plasticized F(2)H(2)Dz-TBP foam packed in column extraction mode. Semiquantitative determination of these metals was also possible using a suitable standard color scale. The effect of diverse ions on the detection of 1 mug mercury(II) and lead(II) by the proposed F(2)H(2)Dz-foam test was critically investigated. The method was satisfactorily applied for the detection of mercury(II) or lead(II) in natural water samples.
authors.affiliation: Department of Chemistry, Faculty of Science, UAE University, P.O. Box: 17551, Al-Ain, United Arab Emirates.
authors.forename: A M
authors.initials: AM
authors.lastname: Kiwan
authors.forename: M S
authors.initials: MS
authors.lastname: El-Shahawi
authors.forename: S M
authors.initials: SM
authors.lastname: Aldhaheri
authors.forename: M H
authors.initials: MH
authors.lastname: Saleh