Hydrothermal Synthesis of Nanostructure Mayenite Calcium Aluminate and Forming as a Support of Catalyst

Document Type : Original Research Paper

Authors

1 Department of Chemical Engineering, Faculty of engineering, University of Sistan and Baluchestan, Zahedan, Iran

2 Department of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, Iran

Abstract

Mayenite (Ca12Al14O33, C12A7) is a promising catalyst support due to its unique structural and electronic properties. However, conventional synthesis routes yield a low specific surface area, limiting access to active sites and reducing catalytic efficiency. In this work, we synthesized nanostructured mayenite via a hydrothermal method and subsequently shaped it into porous tablets using polyvinyl alcohol (10 wt%) and graphite (1 wt%) as pore formers, followed by pressing and calcination at 600 °C. The hydrothermally prepared powder initially showed a surface area of only 6.72 m2/g. After the shaping and calcination process, the surface area increased to approximately 22 m2/g, as confirmed by XRD, BET, and FESEM. Unlike conventional approaches, where sintering during forming reduces surface area, our method relies on in-situ porosity generation during the shaping step. This integrated approach provides a practical, scalable route to produce nanostructured, porous mayenite suitable for high-temperature catalytic applications such as Fischer–Tropsch synthesis.

Keywords


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