NEW GAS-CHROMATOGRAPHIC INSTRUMENTATION FOR STUDYING MASS-TRANSFER PHENOMENA

The new method of reversed-flow gas chromatography for studying hetero geneous catalysis, diffusion, adsorption, evaporation, and other relat ed phenomena, is now applied to study the mass transfer phenomena acro ss the gas-gas, gas-liquid, and gas-solid interphases. As the model ga s solute, the vinyl chloride monomer (VCM), which is of paramount impo rtance in food and environmental sciences, was selected, while the sec ond phase consisted of gaseous nitrogen, liquid water, and solid polyv inyl chloride (PVC). Using appropriate mathematical analysis, the foll owing parameters were determined: (i) Diffusion coefficients of VCM in to nitrogen, (ii) Diffusion coefficients of VCM into water, (iii) Part ition coefficients of VCM between water and nitrogen, (iv) Constants o f Henry's law for the adsorption of VCM by water, (v) Partition coeffi cients of VCM between PVC and nitrogen, and (vi) Enthalpies and entrop ies for the adsorption of VCM on the solid PVC. Comparison of the expe rimental results with those determined theoretically using various emp irical equations, permits the calculation of the accuracy of the metho d used, and gives invaluable information about the rate-determining st ep for the transfer of VCM into water and PVC describing the experimen tal data.