Tracer diffusion coefficients of solutes in supercritical solvents

Based on the free-volume-type diffusion model, new correlations are developed to estimate the tracer diffusion coefficients of liquid and solid solutes in supercritical solvents. The correlations are tested to predict various solute–solvent systems with good results. The input data required for the correlations are the solute molecular weight, temperature, density and the solvent basic properties (molecular weight, critical temperature, critical volume and critical pressure).