Aa. Ensafi et al., Kinetic spectrophotometric method for the determination of oxalic acid by its catalytic effect on the oxidation of safranine by dichromate, SPECT ACT A, 57(9), 2001, pp. 1833-1838
Citations number
16
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
A new catalytic kinetic spectrophotometric method for the determination of
oxalic acid has been described based on its catalytic effect on the redox r
eaction between safranine and dichromate in dilute sulfuric acid media. The
reaction is monitored photometrically by measuring the decrease in absorba
nce of safranine at the maximum wavelength of 530 nm. Under the optimum con
ditions, a calibration graph from 0.10 to 10.00 mug ml(-1) of oxalic acid w
ith a detection limit of 0.08 mug ml(-1) was obtained. The relative standar
d deviation (R.S.D.) for ten replicate measurements of 1.0 and 5.0 mug ml(-
1) oxalic acid was 2.7 and 2.5%, respectively. The purposed method is simpl
e. sensitive, selective and inexpensive. The applicability of the proposed
method was determined by the determination of oxalic acid in spinach and wa
stewater samples with satisfactory results. (C) 2001 Elsevier Science B.V.
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