Solution combustion synthesis of α-cordierite

Abstract

The preparation of α-cordierite powders via combustion route was investigated. Urea, monoethanolamine and triethylenetetramine were used as fuels. The resulting powders were characterized by means of thermal analysis and XRD. Experimental results showed that SiO 2 behaves as an inert material, preventing the formation of 2MgO·2Al 2O 3·5SiO 2 directly from the combustion reaction. Using a fuel mixture of urea and monoethanolamine yielded a poorly crystalline powder (MgAl 2O 4). The phase composition of powders after annealing at various temperatures has shown that the formation of α-cordierite occurs indirectly, via the solid state reaction of spinel and cristobalite. After annealing at 1300 °C for 1 h α-cordierite is virtually the only crystalline phase in the sample obtained with triethylenetetramine. In the sample prepared by using urea and monoethanolamine fuel mixture α-cordierite is the main crystalline phase, alongside traces of spinel and cristobalite. The intermediate formation of μ-cordierite was not observed.