Fabrication of kaolin hollow fibre membranes for bacteria removal

Abstract

This study examines the influence of the particle size, extrusion rate and sintering temperature on the characteristics of kaolin hollow fibre membranes. In addition, the produced membranes were applied for bacteria removal from an aqueous suspension. The milling process reduced the size of kaolin particles from 8.7 to 5.1 ?m and greatly enhanced the morphology and mechanical resistance of the produced membranes. The increase in the sintering temperature up to 1250?C caused crystallographic phase modifications in the crude kaolin, which were mainly assigned to transformations of quartz and kaolinite to mullite and cristobalite phases. The fibres sintered at 1250?C have bending strength of 145MPa, but this relatively high sintering temperature caused a substantial particle densification and drastic decrease of the membrane water permeability. The kaolin hollow fibre membranes enabled almost total removal of the Enterobacter bacteria from an aqueous suspension.

Flat sheet metakaolin ceramic membrane for water desalination via direct contact membrane distillation

“…These observations are in agreement with the X-ray fluorescence (XRF) results in the previous study(Zewdie et al 2021b). It has also been noticed that the beneficiated Ethiopian kaolin powder used in this study consisted of quartz as the non-clay mineral in which the XRD peaks remained for metakaolin-based flat sheet membranes sintered at different target temperatures (1,200-1,500 °C)(Sahnoun & Baklouti 2013;Mohtor et al 2017;Magalhaes et al…”