A new, simple, accurate, fast and sensitive spectrophotometric method has been
developed for the analysis of Pyrocatechol, Resorcinol, and pyrogallolin pure
commercial samples by continuous flow injection analysis. The method was based on
the oxidation of the organic compounds with Ce(IV)sulfate in acidic medium to
formed a brown colored species which determined using homemade Ayah 3SBGR x3-
3D solar cell flow injection microphotometer. Optimum conditions were obtained
using a high intensity green light emitted diode as an irradiation source
forPyrocatechol, Resorcinol, whileblue light emitted diode as an irradiation source for
pyrogallol. The linear dynamic range for the instrument response versus Pyrocatechol,
Resorcinol, and pyrogallol concentrationswere5-40mmol.L-1 while the L.O.D was of
36.63, 17.17, and 41.61ng / sample respectively. The correlation coefficient (r) was
0.9952, 0.9970, and 0.9960 while percentage linearity (r2%) was 99.05%, 99.41% and
99.22%forPyrocatechol, Resorcinol, and pyrogallol respectively. RSD% for the
repeatability (n=8,7, and 8) was 1.4%, 0.63%, 1.78% for the determination of
Pyrocatechol, Resorcinol,andpyrogallol, respectively at concentration of 30 mmol.L-1.
The method was applied successfully for the determination of three organic
compounds in purecommercial samples. A comparison was made between the newly
developed method and the classical method (UV-Vis spectrophotometry) at wave
length 492, 481, and 438 nm forPyrocatechol, Resorcinol and pyrogallolrespectively
of analysis using the standard additions method via the use of paired t-test. It was
noticed that there is no significant difference between two different methods for
analysis three different organic compounds; in addition to no significant difference in
the contribution of the Pyrocatechol, Resorcinol and pyrogallol to the oxidant reaction
path, at 95% confidence level.