ENZYME MASS TRANSFER COEFFICIENT IN AQUEOUS TWO PHASE SYSTEMS: SPRAY EXTRACTION COLUMNS

Fractional dispersed phase hold-up and overall dispersed phase side mass transfer coefficients were measured in 34, 50, 70 and 95 mm i.d. spray columns using an aqueous two phase system. Sodium sulphate-polyethyleneglycol (PEG) (4000)-water formed the aqueous two phase system and amyloglucosidase was used as a solute for the estimation of mass transfer coefficient.

The dispersed phase hold-up (e_D) and volumetric dispersed phase side mass transfer coefficient (K_D) both increased with increasing PEG-rich phase velocity. The e_Dand K_Dawere found to be independent of the column diameter and column height above a certain critical value. An increase in the phase concentration of sodium sulphate and PEG was found to reduce e_Dand K_DEmpirical and semi-empirical correlations for e_D and K_Dahave been developed.