M. Abdulhameed

Preparation and characterisation of inexpensive porous kaolin hollow fibre as ceramic membrane supports for gas separation application

Low-cost, porous ceramic kaolin-based hollow fibre membrane support (HFMS) for gas separation application was developed via phase inversion technique. The ceramic suspensions with various ratios of kaolin to polyethersulfone (PESf) binder (5:1 to 9:1) were extruded and then sintered at 1200 to 1500xa0°C. The HFMSs were characterised by several analyses to investigate the effects of kaolin/PESf ratio and sintering temperature on the sample properties. The results showed that the kaolin/PES ratio and sintering temperature affected the considerable structure and physical properties of the kaolin membrane. It is observed that with increasing sintering temperature, the porosity and gas permeation of the HFMS decreased, while the bending strength and density of the HFMS increased. As a result, a porous HFMS with sufficient mechanical strength and high gas permeation characteristics is achievable if the appropriate kaolin/PESf ratio and sintering temperature are chosen.

Fabrication and characterization of affordable hydrophobic ceramic hollow fibre membrane for contacting processes

Affordable hydrophobic hollow fibre membranes were prepared using kaolin and alumina based ceramic powders via a combined phase inversion and sintering technique, followed by a grafting with fluoroalkylsilane (FAS). The crux of the matter in this paper is to study the changes in the properties of the hollow fibre membranes (gas permeation, mechanical strength, pore size, porosity, tortuosity, morphology, and contact angle) by the addition of alumina (Al2O3) to the pure kaolin with mono or multiparticle sizes. By varying the overall loading and particle size of alumina addition, different morphologies of the membranes were obtained due to the differences in the path lengths during phase inversion process for each solvent and nonsolvent exchange. The successful grafting with FAS was evidenced by the increase in contact angle from nearly equal to zero degree before grafting to 140° after grafting. Kaolin–alumina-4, one of the hollow fibres fabricated in this work, achieved a mean pore size of 0.25 μm with the bending strength of 96.4 MPa and high nitrogen permeance of 2.3×10-5 mol·m-2·Pa-1·s-1, which makes the hollow fibre most suitable for the membrane contactor application.