ANALYSIS OF 2 PHASE MASS-TRANSFER KINETICS BY LOGARITHMIC DRIVING-FORCE BASED ON CHEMICAL THERMODYNAMICS

Interphase transfer kinetics of neodymium and nitric acid was studied using a single drop column with recycling organic phase via an externa l mixing vessel in H2O-HNO3/NaNO3-Nd (NO3)(3-) tri-n-butylphosphate sy stem. Experimental data have been analyzed by two new concepts for dri ving forces for transport: synthesized linear and logarithmic forms. T he former is defined as geometrical-mean driving force, and the latter is the logarithm of the product of reciprocals of concentration ratio s x/x(e) and y/y(e) against equilibrium states in each phase, i. e. ln {(x(e).y(e))/(x.y)}. By applying thermodynamic logarithmic form of dri ving force along reaction coordinate, the net transfer fluxes of neodq miumand nitric acid have been represented by chemical affinity under high ionic strengths over a wide range of solvent loading as flux=flux (f) degrees(1-exp(-A/RT)).