Preparation of MgAl₂O₄ Porous Ceramics for High-Temperature Flue Gas Filtration Application by In-Situ Decomposition Method

Abstract

Porous ceramic filters exhibit excellent prospects for application in the field of hightemperature flue gas filtration. In this study, the MgAl₂O₄ porous ceramics were prepared using α-Al2O3,MgO, and EDTA-MgNa₂ as raw materials by the in-situ decomposition method. The effect of the introduction of EDTA-MgNa₂ on phase composition and microstructure, as well as the correlation between the content of EDTA-MgNa₂ and ceramic properties, was investigated using XRD, SEM, and EDS. The results revealed that the introduction of EDTA-MgNa₂ formed pores, thereby improving gas permeability. Additionally, the addition of EDTA-MgNa₂ was beneficial for the formation of a transitional liquid and promoted sintering, thereby slowing the decrease in compressive strength. The optimal specimen is the ceramic with 10 wt% EDTA-MgNa₂, which exhibits a high porosity of 56.28%, a compressive strength of 10.93 MPa, and a high gas permeability coefficient (8.84 × 10⁻⁹m²).

Keywords

MgAl₂O₄ / Porous ceramics / In-situ decomposition / Flue gas filtration

Acknowledgments

The authors gratefully acknowledge the financial support provided by the Taishan Scholar Program of Shandong Province, Shandong Postdoctoral Science Foundation, Leader of Scientific Research Studio Program of Jinan, University of Jinan Disciplinary Cross-Convergence Construction Projects 2023, the Natural Science Foundation of Shandong Province, the Jinan City-School Integration Development Strategy Project, and the Shandong Provincial Key Research and Development Program.

Author Contributions

Methodology, J.L.; Investigation, J.L.; Writing—Original Draft Preparation, J.L.; Data Curation, J.L., C.Z.; Writing—Review & Editing, W.Z., Z.Z.; Supervision, L.Z., J.K., X.J.; Project Administration, W.Z.; Funding Acquisition, D.Z.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data are available from the corresponding author on reasonable request.

Funding

This research was funded by the Taishan Scholar Program of Shandong Province (No. tsqn202306225),Shandong Postdoctoral Science Foundation (No. SDBX2023025), Leader of Scientific Research Studio Program of Jinan (No. 2021GXRC082), University of Jinan Disciplinary Cross-Convergence Construction Projects 2023 (Nos. XKJC-202301 and XKJC-202311), the Natural Science Foundation of Shandong Province (Nos. ZR2024QE044 and ZR2025QC605), the Jinan City-School Integration Development Strategy Project (Nos. JNSX2023015 and JNSX2023018), and the Shandong Provincial Key Research and Development Program (2025CXGC020107).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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