Kinetic investigation on alkaline hydrolysis of tris-(2,2ʹ-bipyridine)iron(II) in CTAB reverse micellar media

- CTAB reverse micelles catalyzes both hydrolytic and dissociation rates.
- Hydrolytic rate passes maximum value at W = 7.41.
- Dissociation rate decreases with increase in W.
- Independency of rate on CTAB reveals that the reaction occurs in the cavity of water pool.
- Rate increases with increase in Z.

The alkaline hydrolysis of tris-(2,2ʹ-bipyridyl)iron(II) complex has been studied in the CTAB/1-butanol/n-heptane reverse micellar media. The reaction obeys second-order kinetics: first order with respect to each of complex and alkali. Observed pseudo-first order rate constant (kobs) has been determined at different values of W and Z. Rate initially increases and then decreases with increase in W, showing a maximum at W = 7.41. Concentration of CTAB, at constant values of W and Z, has no effect on reaction rate; indicates that the reaction occurs inside the reverse micellar cavity of water pool. Below W = 7.41, both the rate of dissociation and alkaline hydrolysis proceed parallel with a moderate speed. With the increase in Z, concentration of butanol in the water pool increases; decreases the micro-polarity of the water pool and hence increases the rate. The kinetic results are interpreted using the pseudo-phase model.