Iono-molecular Separation with Composite Membranes VI. Nitro-phenol separation through sulfonated polyether ether ketone on capillary polypropylene membranes

The importance of removing and / or separating nitro phenols from aqueous solutions through membranes is substantiated by the multitude of recent research in the field, which broadly justifies both the economic and ecological reasons of such an approach. The present paper outlines the results of the transfer of nitro phenols through a membrane system made up of PPET impregnated polypropylene capillaries (PP) impregnated with sulfonate polyetheretherketone (SPEEK). The experiments were carried out in a PP-SPEEK capillary membrane module, with a useful size of 1 m(2). Determinations made by using a 4 L/min flow rate source at a 5 mg/l nitrophenol concentration and pH 5 or pH 7, and the pH 12 receiving phase and a flow rate of 0.3 L/min, revealed that o- and p-nitrophenol were transferred much faster than m-nitrophenol (the flux is nearly double); the source phase of the system is concentrated in m-nitrophenol, and the receptor phase in o- and p-nitro phenols; the transfer data correlates with the higher water solubility of m-nitrophenol; mono nitro phenols transfer much faster than di nitrophenol, but both the mono and di nitrophenol streams decrease over time; after 4-5 hours of work, the mono nitrophenol concentration triples in the receiving phase, while the 2,4-dinitrophenol concentration doubles in the source phase.