Membranas microporosas híbridas de poliamida aplicadas no tratamento de emulsões oleosas da indústria petrolífera.

Abstract

Microporous membranes were obtained from hybrids of polyamide6 (PA6) with bentonite clay by inversion phase, in the presence of calcium chloride (CaCl2). The membranes were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP) and flow measurements. In precipitation bath used to prepare membranes of pure PA6 were measured some physic-chemical properties. The oily emulsions were characterized by optical microscopy (OM). The results from DSC and XRD for the membranes, confirmed the thermal stability and morphological structure with intercalated and/or partially exfoliated lamella of clay in PA6. From the FTIR results of the membranes it was detected the presence of clay and CaCl2. By SEM and MIP, it was possible to realize an asymmetric membrane morphology comprising of a skin and a porous layer, as well as variations in the average pore diameters with the presence of clay and CaCl2. By means of the contact angle, it was found that all membranes exhibited higher angles for water compared to the angles obtained with oil. In the physic-chemical properties of the solution used as precipitation bath for pure PA6 membrane with CaCl2 and its generate effluent it generated was confirmed the formation of the acid chloride in solution and hydrochloric acid in the precipitation bath. By OM of the emulsions, it was found that the variation in oil concentration and stirring time, did not cause significant changes in the mean diameter of the oil droplets in the conditions studied in this work. In the flow measurements of oil emulsions, it was found that the J/J0 ratio tends to be higher when emulsions of lower concentration are used. The water-oil separation tests, for all membranes, showed a significant reduction in oil concentration in the permeated, thus showing that these membranes have potential for this application.