STUDY OF THE RECIPROCAL SOLUBILITIES IN THE ACRYLONITRILE-PROPIONITRILE-AQUEOUS BUFFER SYSTEM

An empirical additivity rule, previously known for homologues or isome rs of hydrocarbons or alcohols only, has been found applicable for the reciprocal solubilities in acrylonitrile (AN)-propionitrile (PN)aqueo us buffer (B) solution systems. The experimentally determined overall solubility of AN and PN mixtures in B (S-all) can be calculated from t he equation S-all = x(AN)S(AN)+x(PN)S(PN), where S-AN and S-PN are the individual solubilties of AN and PN in B, while x(AN) and x(PN) are t he mole fractions of AN and PN in the organic phase. This additivity r ule is derived theoretically from the chemical potentials of the speci es involved in the equilibrium. Due to the closely related structures of AN and PN, the mixture of these two nitriles show a quasi-ideal beh aviour. The reciprocal solubilities values determined for such systems allow for the calculation of an accurate material balance of PN elect rosynthesis.