Development of an Asymmetric Ultrafiltration Membrane from Naturally Occurring Kaolin Clays: Application for the Cuttlefish Effluents Treatment

Abstract

This work concerns to the development and characterization of support and ultrafiltration membranes from naturally occurring- kaolin clays as principal components. The preparation and characterization of porous tubular supports, using kaolin powder with corn starch as poreforming agent, were reported. It has been found that the average pore size was about 1 μm while the pore volume was 44% for supports sintered at 1150°C with a flexural strength of about 15 MPa. The deposition of the active layer was performed by slip casting method. The rheological study of various coatings with different concentration of kaolin powder, polyvinyl alcohol (PVA) and water under different conditions regarding temperature and stirring time was done. After drying at room temperature for 24 h, the membrane was sintered at 650°C. The average pore diameter of the active layer was 11 nm and the thickness was around 9 μm. The determination of the water permeability shows a value of 78 l/h.m2.bar. This membrane can be used for crossflow ultrafiltration. The application of the cuttlefish effluent treatment shows an important decrease of turbidity, inferior to 1.5 NTU and chemical organic demand (COD), retention rate of about 87%. So, it seems that this membrane is suitable to use for wastewater treatment.