Reaction-bonded robust SiC ceramic membranes sintered at low temperature with coal gangue

Herein, we report an in-situ reaction-bonded SiC membrane sintered at low temperature using a solid waste (i.e. coal gangue) as the sintering aid to form strong neck connections. The effects of sintering temperature and coal gangue proportion on their properties regarding pore size, open porosity, bending strength and pure water permeability were investigated. The single-channel tubular SiC membrane sintered at 1300 degrees C with a coal gangue proportion of 12 wt% was optimal, exhibiting an average pore size of 2.78 mu m, a open porosity of 47.08%, a bending strength of 34.01 +/- 1.3 MPa and a high water permeability of 83967 L m(-2) h(-1) bar(-1). The membrane could completely reject D-50 = 0.87 mu m SiC solids and presented a steady-state water permeability of 458 L m(-2) h(-1).bar(-1). The SiC membrane could be regenerated through ultrasonication and its steady-state water permeability was almost unchanged for 3 cycles, proving its mechanical robustness. This work may appeal to the practical low-cost production of high-performance SiC membranes.

Automated summary

In this study, an in-situ reaction-bonded SiC membrane sintered at low temperature using coal gangue as the sintering aid was developed. The effects of sintering temperature and coal gangue proportion on the membrane properties were investigated. The optimized membrane exhibited excellent pore size, open porosity, bending strength and water permeability, making it suitable for high-performance applications.