| Summary: | 碩士 === 國立中山大學 === 環境工程與科學系 === 85 ===
The kinetics of thermal decomposition of printed circuit board have been investigated thermogravimetrically under various heating rates enther in nitrogen or mixed with 5-15% oxygen in nitrogen. The results show that in pure nitrogen the reaction involves only one stage, with an initial reaction reaction temperature of 564.7-583.6 K and an apparent activation energy at 43.38 Kcal/mol. All of the initial reaction temperature, the reaction rate and its temperature range increase when the heating rate is increased. When oxygen is present, the reaction involves two parallel steps. The fractional conversion at the end of the first reaction is 0.46-0.54, depanding on oxygen concentration. The presence of oxygen anticipates the start of the initial reacton. When the oxygen concentration is increased, the activation energy of the second stage of reaction increases but that of the first stage changes irregularly. The complete rate equation for both stages of reaction was obtained by summing the individual weighted rate equations; the weight factors were determined from the fractional conversion at the end of the first reaction.
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