Cordierite is a frequently used ceramic material, that is often used as a carrier of electrical components due to its low dielectric constant (~ 5) and low temperature thermal expansion coefficient (20·10-7 oC-1). In order to accelerate its sintering process, 5.00 mass% of TeO2 was added to the starting mixtures. The system was tested in two parallel mixtures: one with no added additives, and the other one with TeO2. Mechanical activation of the both mixtures was performed in a high-energy ball mill in time intervals from 0 to 40 min with ball to powder mass ratio 1:40. In order to determine temperature intervals of chemical reactions and phase transitions, differential thermal analyses (DTA) and thermo-gravimetric (TG) analysis were used. Based on the obtained DTA results, it was established that several different processes occur during heating, such as evaporation of physisorbed water, dehydroxylation of Al2O3 based compounds, structural α→β phase transition in crystalline SiO2 and mullite formation. Analysis of these thermally activated processes was performed to determine the relevant kinetic and thermodynamic parameters and investigate the effect of TeO2 addition, thus allowing prediction of optimal sintering conditions to obtain a material with targeted functional properties.