Quasi‐synchronous solid‐state reaction for cordierite powder synthesis

Abstract This study investigates a quasi‐synchronous solid‐state reaction for synthesizing cordierite powder using talc, kaolinite, and Al 2 O 3 mineral powders as starting materials. The thermal reaction proceeded with two different stages according to the Al sources provided by: (1) Al 2 O 3 powders—the first stage starting at temperatures that were considerably lower than 1150°C and (2) kaolinite (mullite)—the second stage starting at temperatures that were higher than 1150°C. The goal is to shift the temperature of the first stage to coincide with that of the second stage by mixing α‐cordierite powder with the starting constituents. Exceeding the authentic reduction amounts of Al 2 O 3 on talc particles leads to a rise in the temperature required to initiate the first‐stage reaction to 1200°C. However, this also eliminates the presence of β‐cordierite and spinel that occur in the first stage and allows for the early fulfilment of α‐cordierite formation in the second stage. The excess SiO 2 released by the second stage compensates for the insufficient SiO 2 required by the first stage, allowing for a smooth processing reaction. Also, a quasi‐synchronous solid‐state reaction for synthesizing cordierite occurs.