Preparation and Characterization of PA66/Alumina Composite Membrane

Abstract

In this study, polymer/ceramic composite membranes were prepared and characterized. The polymer used was polyamide 66 (PA66) deposited by dip coating on the inner surface of α-alumina-based (Al 2 O 3 ) microporous tube. A coating on the ceramic support surface and the formation of the selective layer was analyzed by scanning electron microscopy (SEM) in membranes with one (PA-1) and two layers (PA-2). The results of mercury porosimetry showed that the deposition of the polyamide layers decreases the average pore size. The PA-1 presented an average pore size of 0.35 μm, while the PA-2 presented two peaks of 0.18 and 0.56 μm. Both showed a superior performance than the ceramic support (pore diameter of 0.65 μm). Although, the permeate flux was higher with an impregnation membrane, the number of layers (one or two) just introduced a slight difference in pore statistical analysis. The order of rejection coefficient values for protein molecules is BSA > egg albumin > trypsin. The permeation tests showed that the composite membrane can be applied in ultrafiltration processes with MWCO of 69 kDa.

Hybrid Membranes of Polyamide Applied in Treatment of Waste Water

“…It was observed a similar behavior of the curves for all membranes. The peak on the left side covers a range of diameters with an average of approximately 180 μm which corresponds to the larger pores, which would be the porous support membrane 55 . It was noted that from this peaks is not possible to make an precise analysis of the pores in the support, since they have very large pore sizes above detection range mercury porosimetry.…”

“…It was observed for all membranes an initial decline and a stabilization of the permeated flux after a certain time. The membranes with MMT (1, 3 and 5%) presented higher J/ J 0 compared with PA6 pure membrane and this behavior is due to the formation of larger pores at surface of these membranes 17,18,55 .…”

“…When it comes to a pure solvent and without interaction with the material of the membrane, the permeate flux for a given operating pressure should be constant, since the membrane present a mechanical stability. The PA6 is a hydrophilic polymer, facilitating the absorption of water by reducing the permeate flux rate and size of pores existing on the surface of these membranes 51,[55][56][57][58] . The permeated flux (J) of the membranes for oil/ water emulsion was plotted in the relation to stabilized distilled water flux (J 0 ) and can be observed in Figure 9.…”

Analysis of Composite Membranes in the Separation of Emulsions Sunflower oil/water

“…The ceramic tube was closed on one side and the solution kept in the tube for two hours. Excess solution was removed, and the tube immersed in distilled water for 30 min in order to form the selective layer of PA66 by reverse phase process 20 . The composite membrane remained for 6 h at 30 ºC in a vacuum oven to remove the excess solvent.…”

“…The aim of this study is to obtain a composite filter system with greater selectivity, composed of an inorganic and organic material (α-alumina/PA66). The polymeric layer is responsible for the selectivity, and the ceramic It is important to highlight that the composite membranes with a layer of polyamide 66 (PA-1) and with two layers of polyamide 66 (PA-2) and the ceramic support were characterized in previous study 20 .…”