Preparation of Silicon Carbide and Aluminum Silicon Carbide from a Montmorillonite–Polyacrylonitrile Intercalation Compound by Carbothermal Reduction

Both silicon carbide and aluminum silicon carbide have simultaneously been obtained directly from naturally occurring aluminosilicate by carbothermal reduction for the first time. A precursor of a montmorillonite–polyacrylonitrile (PAN) intercalation compound was heated at 1700°C in Ar. For comparison, montmorillonite–carbon mixtures were similarly heated. α‐SiC, β‐SiC, and Al₄Si₂C₅ formed from the montmorillonite–PAN intercalation compound. Mainly α‐Al₄SiC₄ was obtained with ternary carbides from the montmorillonite–carbon mixtures in addition to a large amount of β‐SiC. Hence, aluminum silicon carbide formation was affected by the mixing condition of the starting materials.