Study of Cr(VI)/tertiary amine reaction kinetics using a modified rotating diffusion cell

An investigation of the equilibrium and kinetic behaviour of Radiamine 6366, a tertiary amine dissolved in decane extracting Cr(VI) from acid solution is presented. Equilibrium and interfacial reaction models were used to describe the results obtained from shake tests and a modified Rotating Diffusion Cell. The modified cell allowed on-line measurement of the concentration in the aqueous phase. A second order forward reaction rate constant of 10(7) M(-1)s(-1) was determined. It was shown that tri-butyl phosphate (TBP) was more surface active than Radiamine 6366 and with TBP addition, the interfacial reaction kinetics were slower.