Enhanced Performance of Fly Ash-Based Supports for Low-Cost Ceramic Membranes with the Addition of Bauxite

• Main Authors: Wan Fan, Dong Zou, Jingrui Xu, Xianfu Chen, Minghui Qiu, Yiqun Fan
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Membranes
• Subjects: low-cost ceramic membranes; fly ash; ceramic supports; bauxite; acid/alkali corrosion resistance
• Online Access: https://www.mdpi.com/2077-0375/11/9/711

Support is a necessary foundation for ceramic membranes to achieve high performance. Finding the optimum balance between high performance and low cost is still a significant challenge in the fabrication of ceramic supports. In this study, low-cost fly ash-based ceramic supports with enhanced performance were prepared by the addition of bauxite. The pore structure, mechanical strength, and shrinkage of fly ash/bauxite supports could be tuned by optimizing the bauxite content and sintering temperature. When the sintering temperature and bauxite content were controlled at 1300 °C and 40 wt%, respectively, the obtained membrane supports exhibited a high pure water permeance of approximately 5.36 m³·m⁻²·h⁻¹·bar⁻¹ and a high bending strength of approximately 69.6 MPa. At the same time, the optimized ceramic supports presented a typical mullite phase and excellent resistance to acid and alkali. This work provides a potential route for the preparation of ceramic membrane supports with characteristics of low cost and high performance.