Co-sintering fabrication of ceramic whiskers enhanced SiC membranes for high-efficiency dust-laden gas filtration

Application of silicon carbide (SiC) ceramic membrane in industrial dust-containing gas filtration has been widely explored. However, its limited gas permeance and complex sintering process hinder its application. In this work, two types of SiC whisker-reinforced ceramic membranes, namely, whisker ceramic membranes (WCMs) and whisker/particle composite ceramic membranes (WPCMs), were prepared using a co-sintering process. By optimizing the co-sintering temperature and SiC whisker contents, defect-free and uniform ceramic membranes were obtained. The mean pore size of WCMs was 12.2 μm with a gas permeance of ∼ 478.0 m³·m⁻²·h⁻¹·kPa⁻¹. The WPCMs exhibited a mean pore size of 3.3 μm with a gas permeance of ∼ 288.0 m³·m⁻²·h⁻¹·kPa⁻¹. SiC whiskers interlaced and connected within membranes, forming a network structure that not only effectively prevented delamination or deformation of the membrane during the co-sintering process but also significantly enhanced the gas permeance of membranes. Additionally, SiC whiskers improved the overall bending strength of membranes and enhanced the rejection of dust particles in the dust-laden gas. The resulting WCMs and WPCMs showed excellent chemical stability and thermal shock resistance. Moreover, the optimized membranes achieved a removal efficiency of 99.99 % for macro (15 μm), micro (2.5 μm), and nano (300 nm) solid particles in the dust-laden gas. This work fabricated high-performance SiC whisker-reinforced membranes that were particularly suitable for gas purification.