Kinetics of the pyrolysis and combustion of göynük oil shale

Thermal behaviour of the glass series (100–y)0.5ZnO·0.1B₂O₃·0.4P₂O₅]·yTiO₂ (with y=0–39 mol% TiO₂) was investigated by DSC and TMA. The addition of TiO₂ results in a non-linear increase of glass transition temperature. The compositional dependences of thermal stability, evaluated by two criteria exhibit two maxima for the glasses doped with 10.7 and 35.9 mol% TiO₂. All the glasses crystallize on heating in the temperature range of 576–670°C. The crystallization mechanism was studied at the glasses with 19.4 and 35.9 mol% TiO₂ and the results showed that surface nucleation mechanism prevails in these glasses over the internal one.