Thermal decomposition and kinetic analysis of sodium propoxides

Sodium n-propoxide and sodium iso-propoxides were synthesized and characterized. Thermal decomposition of these compounds was studied using thermogravimetric technique (TGA) coupled with mass spectrometry (MS) under non-isothermal and isothermal conditions. Various analytical techniques namely atomic emission spectroscopy (AES), infrared spectroscopy (IR), powder X-ray diffraction (XRD), elemental and volumetric analyses were employed to characterize these compounds and their decomposition residues. Kinetic parameters, namely, the activation energy and pre-exponential factor were deduced from the dynamic TGA and MS data. The activation energies derived from isothermal runs for the thermal decomposition of sodium n-propoxide and sodium iso-propoxide were 151.45 ± 2.16 and 128.07 ± 3.44 kJ mol−1, respectively. Decomposition of sodium n-propoxide and sodium iso-propoxide results in the formation of gaseous products of saturated and unsaturated hydrocarbons leaving behind residue consisting of sodium carbonate, sodium hydroxide and free carbon.