KINETICS OF [Co(tpy)2]2+ DISSOCIATION IN AOT/HEPTANE AND CTAB/CHLOROFORM/HEXANE REVERSE MICELLES: A COMPARATIVE STUDY
DOI:
https://doi.org/10.59957/jctm.v61.i4.2026.6Keywords:
[Co(tpy)2]2 , Aquation, water pools, AOT reverse micelles, CTAB reverse micelles.Abstract
A comparative study of the kinetic study of dissociation of [Co(tpy)2]2+ was carried out in two distinct reverse micellar environments, namely AOT/heptane and CTAB/hexane/chloroform. The observed reaction rates were significantly higher in the reverse micellar media compared to an aqueous medium, where the reaction was notably slow and incomplete {kCTAB = 6.9×10-5 s-1 < kAOT = 31.5×10-3 s-1}. The enhanced reaction rate in reverse micelles was explained in terms of the lower dielectric constant of water present in the reverse micelles. Analysis revealed that, the rate of reaction decreases with increasing the W {= [H2O]/[surfactant]}in both the reverse micellar media. The reaction rate increases with the concentration of the anionic surfactant (AOT) but independent of the concentration of the cationic surfactant (CTAB). The dependence of rate of reaction on surfactant concentration in the case of AOT
has been explained on the basis of electrostatic interactions between electro positively charged complex [Co(tpy)2]2+ and charge of anionic micellar interface.
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