Removal of indigo carmine and heavy metals by ultrafiltration ceramic membrane

Abstract

This article describes the preparation and characterization of a porous ceramic multilayer ultrafiltration membrane and its performance on indigo carmine and heavy metals removal.

The first step of elaboration consists in preparing a high quality macroporous support from Moroccan clay. The microporous interlayer is prepared by slip casting from zirconia commercial powder suspension. The active ultrafiltration toplayers are obtained by sol-gel route using ZnAl₂O₄ and TiO₂ mixed sols. The performance of the ultrafiltration membrane (TiO₂ (50 %)-ZnAl₂O₄ (50 %)) was evaluated by water permeability, thickness, pore diameter and molecular weight cut off (MWCO). The water permeability measured for this composite membrane is 9.42 l/(m²·h·bar), the thickness is less than 700 nm, the pore diameter is centred near 5nm and the MWCO was about 4500 Da. The final part of this study consists in studying the efficiency to remove Cr(NO₃)₃, Ni(NO₃)₂, Cd(NO₃)₂ and indigo carmine colorant from wastewater.