Flow Injection Spectrophotometric Determination of Cobalt with 2-(5-Bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)aniline
Analytical Science and Technology / Analytical Science and Technology, (P)1225-0163; (E)2288-8985
1993, v.6 no.1, pp.57-63
Kang, Sam Woo
Kim, In Yong
Han, Hong Seok
Lee, Seung Seok
Kang,
S. W., Kim,
I. Y., Han,
H. S., &
Lee,
S.
S.
(1993). Flow Injection Spectrophotometric Determination of Cobalt with 2-(5-Bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)aniline. , 6(1), 57-63.
Abstract
Spectrophotometric determination of cobalt by flow injection method is described. 2-(5-Bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino) aniline rapidly forms a water-soluble complex with cobalt in $NH_3-NH_4Cl$ buffer solution at pH 10.5. The absorption maxima of this complex is at 545 nm with molar absorptivity of $58000L\;mol^{-1}\;cm^{-1}$. The calibration curve of cobalt is linear over the range of 0.1 to 0.6ppm and the detection limit is 25ppb. The relative standard deviation is ${\pm}0.72%$ for 0.5ppm and the sampling rate is $60samples\;hr^{-1}$. The interfering effect of some cations and anions was investigated. Ni(II), Cu(II), Fe(III) and $CN^-$ interfered severely. The interfering effect of these matallic ions could be decreased by adding $1.0{\times}10^{-3}M$ EDTA solution to the carrier stream.
- keywords
-
Flow Injection,
Spectrophotometry,
Cobalt,
5-Br-PSAA