Separación de compuestos organoclorados volátiles de disoluciones acuosas mediante pervaporación

Abstract

This work has as main objective the kinetic analysis of the separation of volatile organochlorine compounds: chloroform, dichloromethane and trichloroethylene from aqueous solutions of by pervaporation using commercial membranes made of silicone rubber. Initially a comprehensive study of the pervaporation of aqueous solutions of chloroform has been done. Two systems have been used with the membrane geometry different: i) A flat membrane cell with outward radial flow between two plates. The liquid phase mass transfer coefficients were correlated with the operating variables flow rate and temperature using dimensionless groups. ii) Pervaporation in hollow fiber devices. A systematic methodology has been applied to the analysis of the mass transfer rate of the separation process. A mathematical model resulting from the solution of the continuity equation of the feed phase flowing in laminar regime through the hollow fiber module has been proposed. Finally, a generic model is derived for studying the mass-transfer kinetics of the pervaporation of multicomponent mixtures. Applying it to the pervaporation of dilute mixtures of VOCs permits the estimation of the representative mass-transfer parameters and discrimination of the relative importance of the mass-transport resistances to the pervaporation flux as a function of operation variables