Sabeur Khemakhem

Elaboration of new ceramic microfiltration membranes from mineral coal fly ash applied to waste water treatment

This work aims to develop a new mineral porous tubular membrane based on mineral coal fly ash. Finely ground mineral coal powder was calcinated at 700 degrees C for about 3 h. The elaboration of the mesoporous layer was performed by the slip-casting method using a suspension made of the mixture of fly-ash powder, water and polyvinyl alcohol (PVA). The obtained membrane was submitted to a thermal treatment which consists in drying at room temperature for 24 h then a sintering at 800 degrees C. SEM photographs indicated that the membrane surface was homogeneous and did not present any macrodefects (cracks, etc...). The average pore diameter of the active layer was 0.25 microm and the thickness was around 20 microm. The membrane permeability was 475 l/h m(2) bar. This membrane was applied to the treatment of the dying effluents generated by the washing baths in the textile industry. The performances in term of permeate flux and efficiency were determined and compared to those obtained using a commercial alumina microfiltration membrane. Almost the same stabilised permeate flux was obtained (about 100 l h(-1)m(-2)). The quality of permeate was almost the same with the two membranes: the COD and color removal was 75% and 90% respectively.

Purification of industrial effluent by microfiltration and ultrafiltration ceramic membranes: comparative study between commercial and elaborated Tunisian clay membranes

Abstract Industrial effluents treatment was investigated using ceramic Microfiltration (MF) and Ultrafitration (UF) tubular membranes. The comparison of performances between commercial ceramic membranes based on alumina material and elaborated ones based on Tunisian clay material was studied. MF and UF tests applied to cuttlefish effluent treatment were carried out respectively with 0.2 μm and 5 nm commercial membranes and 0.18 μm and 15 nm prepared membranes. The results show that for the two processes, the performances in term of permeate flux and quality of the treated wastewater using clay membranes was a little better than that obtained with commercial one.

Surface modification of microfiltration ceramic membrane by fluoroalkylsilane

ABSTRACTMembrane 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 0.2 μm 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 disti...

Treatment of Industrial Effluents by MF and UF Ceramic Membranes:Comparative Study using Commercial and Elaborated Tunisian ClayMembranes

Industrial effluents treatment was investigated using ceramic Microfiltration (MF) and Ultrafiltration (UF) tubular membranes. The comparison of performances between commercial ceramic membranes based on alumina material and elaborated ones based on Tunisian clay material was studied. MF and UF tests applied to cuttlefish effluent treatment were carried out respectively with 0.2 μm and 5 nm commercial membranes and 0.18 μm and 15 nm prepared membranes. The results show that for the two processes, the performances in term of permeate flux and quality of the treated wastewater using clay membranes was a little better than that obtained with commercial one.

Synthesis and Characterization of a Novel Hydrophobic Membrane: Application for Seawater Desalination with Air Gap Membrane Distillation Process

Ceramic membranes are usually prepared from metal oxides like alumina, zirconia, titania. The development of membrane processes is generally limited because the price of the commercial membranes is too expensive, which is particularly true for the inorganic membranes. One of the challenges for future development of the inorganic membranes consists to prepare membranes of low cost made with natural non-expensive material (Khemakhem, & al., 2009; Saffaj & al., 2006). Rapid development and innovation have already been realized in this area (Cot, L.; 1998). Clay minerals are a well-known class of natural inorganic materials, with well-known structural adsorption, rheological and thermal properties (Brigatti & al., 2006; Wang & al., 2007). Research on clay as a membrane material has concentrated mainly on pillared clays (Tomul & al., 2009). Studies of membranes prepared entirely from natural clays have just started (Mao & al., 1999). These materials originally have a hydrophilic character due to the presence of the surface hydroxyl (–OH) groups, which can link very easily water molecules ( Larbot& al., 2004; Picard & al., 2004).