A model that describes the pure evaporation kinetics is introduced. This model takes into account gas diffusion and convective gas transport; it describes the evaporation kinetics under the general conditions of thermogravimetric measurements. The model is used to determine the equilibrium vapour pressure in a relatively wide temperature range. The validity of the model is checked against experimental data of triethanolamine (TEA) and water evaporation. The applicability of isoconversional methods to the evaporation kinetics is also studied. Besides, it is shown that the degree of TEA decomposition depends on the surrounding atmosphere and on the conditions for gas evaporation; the easiest the gas evaporation, the smallest the degree of decomposition.In view of the volatiles formed, a reaction pathway is proposed for the thermal decomposition of TEA.

Thermal decomposition of cerium triethanolamine complexes to cerium oxide, CeO2, in inert and oxidative atmospheres has been investigated by thermogravimetry combined with infrared evolved gas analysis; the main volatiles formed during thermal decomposition have been identified. Intermediates and final products have been characterized by infrared spectroscopy, X-Ray diffraction and elemental analysis. Several overlapping steps occurring along decomposition path have been identified and plausible reaction pathways are presented. It will be shown that decomposition starts around 200ºC independently of the atmosphere, but the endset temperature depends on the gas composition: the more inert the atmosphere the higher the endset temperature. Finally, the effect of the temperature and amount of triethanolamine used during compound synthesis is discussed.

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