Tris(2,2'-bipyridine) complex of iron(II) was found to cause an increase in the chemiluminescence (CL) emission of luminol dispersed in the reversed micellar medium of cetyltrimethylammonium chloride (CTAC) in 1:1 (v/v) dichloromethane-cyclohexane/water, when the iron(II) complex in dichloromethane was mixed directly with the reversed micellar solution containing luminol. Visible absorption measurements showed that, when dispersed in the CTAC reversed micellar medium, the iron(II) complex dissociates easily. In the reverse micelle, subsequently the free iron(II) ion produced may catalyze the CL oxidation of luminol even in the absence of hydrogen peroxide.
View Article and Find Full Text PDFTo eliminate the use of chlorinated hydrocarbons, we have improved the method for the flow-injection (FI) determination of iodine based on the chemiluminescence reaction of iodine with luminol in a chloroform-free reversed micellar medium of the surfactant cetyltrimethylammonium chloride (CTAC) using a mixture of 1-hexanol-cyclohexane as a bulk solvent. The FI procedure used simply involves the mixing of an iodine solution in cyclohexane with the chemiluminescent reagent solution of luminol in the reversed micellar medium of CTAC in 0.38 M 1-hexanol in cyclohexane/water (buffered with sodium carbonate).
View Article and Find Full Text PDFThe effects of illumination time, temperature, catalyst concentration, and pH on the on-line photocatalytic dehalogenation of iodinated aromatic compounds in a near-UV-illuminated titanium dioxide (anatase type) aqueous suspension were monitored via the iodine-luminol chemiluminescence (CL) reaction in a reversed micellar medium, and a new, automated, rapid, and efficient method was developed. A water-cooled, 400-W high-pressure Hg lamp was used as an internal light source. The flow procedure involved the following: (1) photocatalytic dehalogenation/degradation of the iodinated compound by the near-UV-illuminated titanium dioxide and the production of iodide species, (2) oxidation of iodide into iodine, (3) extraction of iodine into cyclohexane, (4) membrane separation of the iodine-containing organic phase from the aqueous phase, and (5) the detection of iodine using the luminol CL reaction in the reversed micellar solution of cetyltrimethylammonium chloride in 6:5 (v/v) chloroform-cyclohexane/water buffered with sodium carbonate.
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