Simple detection of trace Pb2+ by enrichment on cerium phosphate membrane filter coupled with color signaling.
A Pb(2+) selective membrane filter was fabricated from the fibrous CeO(H(2)PO(4))(2).2H(2)O (CeP) crystals by blending with cellulose fiber. Enrichment of ppb level of Pb(2+) was achieved simply by filtration of aqueous sample solution through the membrane filter. Pb(2+) was strongly retained on the membrane filter by accommodation into the interlayer gallery of a CeP crystal. Visual detection of the enriched Pb(2+) was achieved by subsequent color signaling as PbS deposit upon treatment of the membrane filter with 3% Na(2)S solution. The analytical procedure and sample treatment conditions were optimized with respect to pH of the sample solution, filtration rate and masking of interfering ions. Detection of 20 ppb of Pb(2+) was not interfered by the presence of 1000-fold of Ca(2+), Mg(2+), and up to 100-fold of Fe(3+)and Cu(2+) by masking with 1 x 10(-3) mol dm(-3) of iminodiacetic acid (IDA). Most anions including phosphate (20 000 times) did not interfere with the determination of Pb(2+). The present simple method was applied to the determination of Pb(2+) in real samples like mine valley water.
Suzuki
Toshishige M
TM
Research Center for Compact Chemical Process, National Institute of Advanced Industrial Science and Technology, Sendai 983-8551, Japan.
Llosa Tanco
Margot A
MA
Pacheco Tanaka
David A
DA
Hayashi
Hiromichi
H
Takahashi
Yukiko
Y
D002563:Cerium; D003124:Colorimetry / Q000295:instrumentation / Q000379:methods; D005374:Filtration; D007854:Lead / Q000032:analysis*; D008906:Mining; D010710:Phosphates; D014131:Trace Elements / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D010710:Phosphates; D014131:Trace Elements; D014874:Water Pollutants, Chemical; D007854:Lead; D002563:Cerium; C048083:cerium phosphate