Fabrication of low-cost granite dust ceramic hollow fibre membrane: Effects of sintering temperature

Ceramic hollow fibre membrane (CHFM) is associated with many advantages such as better mechanical and thermal stabilities. However, the cost of the CHFM is very high owing to expensive raw materials and high sintering temperature. In this study, granite dust, a waste from stone industry was selected as a raw material to reduce the cost of ceramic membrane. The influence of sintering temperature on the physical properties of granite dust CHFM (GD-CHFM) was also investigated. The GD was subjected to XRD, XRF, and TGA analysis in order to understand the psychochemical properties of the GD. The GD-CHFM was prepared via a phase inversion and sintering method. Then, the GD-CHFM precursors were sintered at various temperature ranging between 1050 °C and 1150 °C. The effects of sintering temperature on the morphology, porosity and mechanical strength were systematically investigated. From the SEM images, the membranes exhibited symmetric structure where the average grain sizes were found to increase with sintering temperature. It was also realized that when the sintering temperature exceeded 1150 ℃, the GD-CHFM starts to melt. The volumetric porosity was found to decrease with sintering temperature due to the densification of pores. The increased in bending strength can be related with the decreasing of porosity in the sintered GD-CHFM. The mechanical strength of GD-CHFM sintered at 1150 °C was comparable with the CHFMs sintered at higher temperature (greater than 1400 °C). This indicates that the cost of GD-CHFM production can be reduced significantly, making it economically attractive for the future commercialization of GD-CHFM.