Surface modification of microfiltration ceramic membrane by fluoroalkylsilane

Membrane separation performances regarding selectivity and permeate flux depend on the membrane texture and chemical composition of the material used for membrane elaboration. The surface properties of composite microfiltration membrane zirconium/mud of hydrocyclone laundries of phosphates with average pore diameter of 0.2μm was chemically modified to change its hydrophilic feature into hydrophobic by grafting 1H,1H,2H,2H—perfluorodecyltriethoxysilane molecule (C8). Observation by scanning electron microscopy showed a sharp decrease of the grafted membrane pore size. Thermogravimetric analysis was used as a technique to identify the grafted silane groups. IR analysis allowed qualitative identification of the presence of link characteristics of incorporated silanes. The determination of the contact angle on the grafted membrane surface proved the hydrophobic character since its value increases from 25° to more than 150°, respectively before and after grafting. The membrane permeability using distilled water decreased from 720 L h−1 m−2 bar−1 before grafting to 7 L h−1 m−2 bar−1 after surface modification.