Pyrolysis Activation Energy of Cellulosic Fibres Investigated by A Method Derived from The First Order Global Model

The pyrolysis kinetics of cellulosic fibres, a natural cotton yarn (NCY) and a mercerized cotton yarn (MCY), has been explored with a modified first order global analysis method (FOG), via a series of non-isothermal experiments, using thermogravimetric analysis (TGA). The modified FOG analysis routine was developed to overcome discrepancy in heating rate and difference between exact results and approximations in integrals. The intrinsic pyrolysis activation energy, with temperature range tending to zero, was found to be independent of heating rate and approximation used, giving average values of 153 ± 2 kJ/mol for NCY and 192 ± 7 kJ/mol for MCY. This proves the applicability of the reported analysis routine under the conducted TGA measurements. The reasons for different values were hypothesized to be the difference in chemical composition and crystalline structure. The findings provide a new approach in the investigation on pyrolysis kinetics of biomass and factors impacting their pyrolytic behaviour.

纤维素纤维（包括天然棉纱线（NCY）和丝光棉纱线（MCY））的热解动力学已通过一系列非等温实验，采用热重分析（TGA）技术，结合改进的一级全局分析方法（FOG）进行了探究。改进的FOG分析程序旨在解决加热速率的差异以及积分中精确结果与近似值之间的偏差问题。研究发现，当温度范围趋近于零时，本征热解活化能与加热速率及所用近似方法无关；NCY的平均本征热解活化能为153±2 kJ/mol，MCY则为192±7 kJ/mol。这证实了所报道的分析程序在本次TGA测量条件下的适用性。两种纤维活化能数值差异的原因被推测为其化学成分和晶体结构的不同。该研究结果为生物质热解动力学及其热解行为影响因素的研究提供了一种新方法。