Preconcentration of Iron in Some Drug and Water Samples by Coprecipitation with Magnesium Hydroxide Before Spectrophotometric Determination
Abstract
A method was purposed for preconcentration and determination of iron, in this
study. The method consist of these steps respectively: I) Coprecipitation of
the iron present in the sample with Mg(OH)2 collector. II)
Seperation of the precipitate by centrifuging. III) Solving the precipitation
in acid. IV) UV-VIS spectrophotometric determination of the iron concentrated
in the resultant lower volume solution using its complexation with thiocyanate.
The effects of factors such as centrifugation time, pH and Mg concentration on
the absorbance signal were investigated and the optimum values of these factors
were determined. Total iron in the sample was brought single oxidation state
(Fe(II) or Fe(III)) before coprecipitation procedure. Calibration
curve was derived for both of the proceses. The detection limit and working
range for the proposed method were found to be 0.01 mgL-1 and
0.03-0.3 mgL-1 respectively. The proposed method was applied to tap
water, mineral water samples and Rennie anti-acid drug tablet. The accuracy of
the method was tested by analyte spiked method. The accuracy results in terms
of Recovery % are between 90-100%. Mostly the relative standart deviations (RSD
%) values do not exceed 5%.
Keywords
References
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