Incorporation effect of olive pomace on the properties of tubular membranes

Abstract

This study aims at investigating the use of abundant materials such as clay and pomace olive in the preparation of tubular membranes. The use of olive pomace as a porosity agent produces a porous clay tubular membrane with controlled microstructure (porosity and pore size). The raw materials were characterized by physicochemical methods, namely X-ray fluorescence, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TGA/DTA) and scanning electron microscopy (SEM). These techniques show that the studied clay consists essentially of quartz; calcite and kaolinite. Tubular membranes made from a mixture of clay / X% (0, 4, 6, 8, 10 and 12 %) by weight of olive pomace were prepared by extrusion and sintered at different temperatures (700, 800, 900 and 1000 °C).The results obtained show that the sintered tubular membranes at 1000 °C are characterized by range value of shrinkage is 0.75–3.94 %, apparent porosity of 5.5–41 % and the reduced bending strength from 23.26 to 7 MPa depending on the olive pomace content. The pore structure was analyzed by SEM and the chemical resistance tests were performed in a sodium hydroxide solution and a nitric acid solution; they have better chemical resistance to alkalis but less resistance to acids. These results allow to conclude that the tubular membranes containing 8 % of olive pomace are promising porous ceramic structure for wastewaters filtration applications due to their excellent properties.