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专业: 污染控制化学

[交流] 有关TPD计算活化能的问题

最近投了篇文章，审稿人对我的实验数据的处理提出了质疑。我是利用TPD实验做噻吩的脱附实验，并根据不同升温速率下的峰值温度计算了脱附活化能。审稿人认为：程序升温脱附噻吩实验中我没有确认脱附的都为噻吩，有可能吸附过程噻吩发生了反应变成了其他的物质；利用不同升温速率下的峰值温度计算活化能必须首先证明脱附过程的再吸附对脱附的影响不大且必须证明脱附过程不是扩散控制（这两个我自己认为都不是很好证明）。采用方法进行实验我也是参照文献进行实验的，现在就不能确定审稿人说的是不是有道理，我应当如何进行回答，希望达人指教。
原话如下：

Based on equation (4) the activation energy values for desorption are calculated under the assumption that the desorption process follows first order kinetics. It should be noted however that equation (4), (presumably taken from the work of Cvetanovic and Amenomiya, Adv. Catal. 17 (1967) 103) holds only when readsorption does not occur (in case of readsorption occurring freely or diffusional control, the shift of the peak temperature originated by an increase in the heating rate cannot be used for determining the activation energy of desorption). There is no evidence supporting such assumptions (i.e. readsorption not occurring and first order kinetics for desorption). Furthermore, it should be noted that (i) a TCD-equipped apparatus is used for obtaining the TPD profiles, i.e. there is no way for revealing whether the desorbed matter is actually thiophene, and (ii) it is quite probable that a variety of products forms during the desorption process, as reported in the literature for thiophene-saturated acidic zeolites (see the papers of Iglesia and coworkers on this topic, for instance: Chica et al., Langmuir, 20 (2004) 10982; Chica et al., Appl. Catal. B: Environ. 60 (2005) 231). It is hence clear that the TPD technique is unappropriate for determining the strength of the thiophene-adsorbent interaction.

另外：他提到我是利用TCD检测器进行检测，其实我是利用FID检测器的，审稿人看错了。

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