Membranes have been widely used in the treatment of industrial effluents. However, there are still some limitations in the separation and permeability with respect to these effluents. Therefore, this study investigated the addition of 1% and 5% of an inorganic filler (clay) in polyethersulfone polymer membranes. By contact angle analysis, it was observed that the clay influenced the hydrophilicity of the membrane. The presence of the clay had an important role in the morphology of the membrane, modifying and favoring a greater quantity of pores and macropores for the porous support. For the tensile test, it was seen that the high clay content decreased the membranes properties. The flow tests, having a flow stabilized around 300 L/h·m² for membranes containing clay, evidenced the efficiency of the membrane for the treatment of indigo blue, representing a 200% increase in relation to polyethersulfone membrane. The membrane containing 1% of clay presented the highest level of rejection to the effluent, around 94.0%. Thus, it was evident that the addition of montmorillonite clay modified the membrane structure contributing to a higher selectivity and permeability.

Polyethersulfone (PES) hollow fiber membranes were produced, containing 3% of two types of clay (Brasgel PA - MMT and Cloisite NA - CLNa), in order to modify the characteristics of the polyethersulfone membrane. By means of the X-ray diffraction, it was possible to observe an exfoliated and/or partially exfoliated structure in the membranes containing clay. From the analysis of contact angle, it was possible to notice an increase in the hydrophilicity of the membrane with the introduction of the clay. Through scanning electron microscopy (SEM), the morphology of the porous support of the membrane was modified with addition of clay, favoring greater uniformity of the pores and fingers. In the flow measurements with distilled water, the membranes with clay obtained the highest flows, being the greater flow with the Cloisite Na clay (~22 L/h.m²) and was in agreement with the contact angle results. In the analysis of permeation with the oily emulsion, the membrane with Brasgel PA clay in its structure presented the greatest flow (~16 L/h.m²) and the membrane with Cloisite Na presented the greatest yield (78.28%). Therefore, the clay acted by modifying both the morphology and the hydrophilicity of the polyethersulfone membrane, improving flow and yield.

Membranes of polyamide 6 and its nanocomposites with 3 and 5% of clay were obtained by the phase inversion method using distilled water and solvent as the coagulation bath, 10 and 30% of acid was used, in order to change the membranes morphology/porosity. By XRD analysis, the obtained nanocomposites showed an exfoliated and/or partially exfoliated structure, it was also seen two characteristics peaks of the polyamide 6 phases (α and γ). For the membranes, the characteristic peak γ of the membrane disappeared, being evident the peaks α₁ and α₂. By SEM the PA6 membrane almost doesn't have pores in its surface, with an addition of clay had an increase in the quantity of surface pores. In the cross section of the PA6 membrane, an extremely thin selective layer, adding the clay the selective layer became thicker and a better defined porous support was obtained. From the acid in the coagulation bath the PA6 membrane continued with a few pores structure. For the nanocomposites there was an increase in size and a better uniformity of the pores. In the cross section the presence of the bath decrease the membrane filtering, also modifying a uniformity of the pores.

The use of a coagulation bath and the inclusion of polyvinylpyrrolidone (PVP) are key in influencing the structural features and operational behavior of polymeric membranes. Previous investigations involving polysulfone (PSf) and polyethersulfone (PES) membranes emphasize the importance of these elements. This study investigates the effect of solvent content in the coagulation bath and the addition of PVP on the properties of flat‐sheet PSf/PES blend membranes in water/oil separation applications. This research examines how varying the solvent concentration in the coagulation bath, combined with PVP incorporation, influences the characteristics of PSf/PES blend flat membranes applied to water/oil separation. Membranes were prepared using both pure polymers and PSf/PES blends and characterized through scanning electron microscopy (SEM), permeation evaluations, and separation performance analyses. The incorporation of PVP enhanced the hydrophilic nature of the membrane, evidenced by a decrease in water contact angle (WCA). In addition, the oil contact angle (OCA) of membranes with elevated PVP content demonstrated greater underwater oleophobicity. SEM analysis revealed structural modifications, including variations in pore size and density, as well as changes in finger‐like structures and macropores. Membranes containing PVP exhibited greater pore uniformity compared to the pure membrane, resulting in a more pronounced enlargement of the average pore size, which contributed to higher fluxes while maintaining oil removal performance. Furthermore, a connection between viscosity, pore structure, and flux outcomes was explored, correlating these factors with demixing kinetics. Membranes containing PVP exhibited higher fluxes, confirming its positive impact on separation efficiency.