Enhancement of microfiltration performances of pozzolan membrane by incorporation of micronized phosphate and its application for industrial wastewater treatment

Abstract

The present paper reports the enhancement of low-cost ceramic microfiltration pozzolan membrane by incorporation of micronized phosphate. The flat membrane was obtained by dry uniaxial pressing process and sintering. The effect of sintering temperature (900–1100 °C) and MP addition (10–40 wt.%) on membrane properties such as porosity, microstructure, mechanical strength and permeability were investigated. Experimental results showed that temperature increasing significantly improves microstructure, mechanical strength and permeability of pozzolan membrane until 1050 °C. Importantly, the incorporation of micronized phosphate in pozzolan matrix considerably diminishes membrane pore size while the porosity is preserved. Therefore, membrane competitiveness can be enhanced in terms of selectivity and permeability. Referring to results, it was found that optimized membrane (20 wt.% of micronized phosphate and sintered at 1050 °C) has a porosity of 32.07%, an average pore diameter of 1.33 μm and a water permeability of 1732.5 L/h.m2.bar. As application, optimized membrane was applied for microfiltration of aluminum chloride suspension and wastewater of tannery industry. Filtration results showed that the membrane could approximately reject the totality of turbidity (99% for aluminum chloride suspension and 97% for tannery effluent). Finally, based on its promising proprieties, its excellent filtration efficiency as well as its low cost, the obtained membrane could be recommended as alternative membrane for clarification of industrial wastewater.