This study employed thermogravimetric analysis (TGA) alongside the Coats-Redfern method (CRM) to investigate the thermal degradation's kinetics and thermodynamics of fibers extracted from the flower stalk of Agave americana (FSAA). We explored FSAA fibers' thermal behavior across varying heating rates (HRs) to elucidate complex reaction mechanisms and estimate critical parameters. TGA experiments at 5, 10, and 20 °C/min HRs reveal a multi-step breakdown process supported by solid coefficients of determination ( > 0.99). Activation energy values, ranging from 83.6 to 210.1 kJ/mol, vary with HR, providing insights into thermal decomposition kinetics. Thermodynamic parameters, including variations in entropy (ΔS), Gibb's free energy, and enthalpy, shed light on spontaneity and energy transfer during the process. Negative ΔS values suggested reduced disorder during thermal decomposition. This study represented a novel investigation into the thermal behavior of fibers extracted from the FSAA for the first time, using CRM in conjunction with TGA. Through comprehensive analysis, we elucidated the kinetics and thermodynamics of FSAA fiber degradation across various HRs. Our findings shed light on the intricate reaction mechanisms underlying FSAA fiber decomposition, providing valuable insights for potential applications in biofuel production and composite materials.

中文翻译：

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美洲龙舌兰纤维的缓慢热解：在不同加热速率下使用涂层-雷德芬方法进行动力学和热力学分析


本研究采用热重分析 (TGA) 和 Coats-Redfern 方法 (CRM) 来研究从龙舌兰花茎中提取的纤维 (FSAA) 的热降解动力学和热力学。我们探索了 FSAA 纤维在不同加热速率 (HR) 下的热行为，以阐明复杂的反应机制并估计关键参数。 5、10 和 20°C/min HR 下的 TGA 实验揭示了由固体决定系数 (> 0.99) 支持的多步骤分解过程。活化能值范围为 83.6 至 210.1kJ/mol，随 HR 变化，提供了对热分解动力学的深入了解。热力学参数，包括熵 (ΔS)、吉布斯自由能和焓的变化，揭示了该过程中的自发性和能量转移。负 ΔS 值表明热分解过程中无序度减少。这项研究首次将 CRM 与 TGA 结合使用，对从 FSAA 中提取的纤维的热行为进行了新颖的研究。通过综合分析，我们阐明了 FSAA 纤维在不同 HR 下降解的动力学和热力学。我们的研究结果揭示了 FSAA 纤维分解背后的复杂反应机制，为生物燃料生产和复合材料的潜在应用提供了宝贵的见解。