Dynamic TG investigations were carried out to elucidate the mechanisur
of thermal decomposition of aluminium sodium sulphate crystallohydrat
e. Shimadzu 31H and MOM Derivatograph X-ray diffraction and other tech
niques were used to determine data on the decomposition, activation en
ergy, structure and phases in the solid products. Isothermal study in
the temperature ranges 883-958 K and 983-1113 K in air or a reducing g
as atmosphere revealed different reaction mechanisms. Depending on the
experimental conditions, mainly Al2O3 can be obtained.