Physico-chemical characterisation of selective TiO2 layer on kaolin-based ceramic membranes

Abstract

The selective layer in a ceramic membrane is crucial for separation and filtration processes, as it endows the membrane with specific properties and functions, determining its selectivity and suitability for various applications. This study aimed to investigate the impact of the type of composition used to create a selective layer on low-cost clay ceramic membranes and to determine their physicochemical properties and permeability. In this study, a ceramic membrane substrate based on kaolin was synthesized and characterized using XRD, thermal analysis, and IR spectroscopy, and its mechanical properties were also tested. Selective layers on the ceramic membrane were synthesized with various compositions using spin-coating. They were characterized using IR spectroscopy, diffuse reflectance absorption spectrum, and scanning electron microscopy (SEM). The SEM images of all samples show a dense structure typical of clay materials. These images indicate that the composition and number of layers have minimal impact on the morphology in this case. The obtained ceramic membranes are characterized by a pore size ranging from 50 – 200 μm. The permeability of the ceramic membrane support is 40 cm3/min·cm2, which decreases with the application of selective layers. Selectivity by turbidity increases from 32% to 66.4%.