Papers by Keyword: Pyrolysis Kinetic

Abstract: Three types of unsaturated polyester matrix, ortho phthalic, iso phthalic, and vinyl ester, reinforced with glass fiber laminated composite waste have been subjected to investigate thermal decomposition behavior and kinetic parameters using non-isothermal thermogravimetric analysis from an ambient to temperature 900°C under nitrogen atmosphere at the passing flow rate of 20 ml/min. The results showed that the major decomposition range of the unsaturated polyester matrix was from 260 to 445°C, depending on a heating rate and the different types of polyester matrix. Regarding their chemical structure, ortho phthalic polyester started to degrade at lower temperature (260-280°C) than iso phthalic and vinyl ester (300-350°C). The remaining solid residual contained glass fiber which could not degrade under experimental conditions. The maximum rate of weight loss was increased with increasing heating rate. The activation energy for decomposition of ortho, iso phthalic, and vinyl ester composites was 168, 172, and 176 KJ/mol, respectively.

Abstract: The TG and DTG curves of self-made ZnO precursor were studied by the thermo-gravimetric analysis method in N2 atmosphere from 25°C to 650°C at the heating rate of 5, 10 and 15°C/min. The TG curve showed that the decomposition process started at about 150°C and finished at 300°C, in accordance with the temperature range of the decomposition from basic zinc carbonate to zinc oxide. The first level chemical reaction based on Coats-Redfern method was applied to estimate the activation energy of the decomposition. The correlation factor was about 0.99, and the calculated average activation energy was 33.89kJ/mol. Active zinc oxides were perpetrated by microwave heating at 350°C for 30min. Their composition and surface morphology were investigated by using scanning electron microscope and X-ray diffraction and its quality can reach the first-grade standard of HG/T2572-94.