The reasons for the intrinsic reactivity differences in coal char conversion under an O₂/H₂O atmosphere compared with that under an O₂/CO₂ or O₂/N₂ atmosphere have been investigated in a thermogravimetric analyzer by a simple variable activation energy (SVAE) method combined with an adsorption/desorption reaction mechanism. The results show that only CO₂ or H₂O chemisorption occurred in the non-isothermal experiments, not gasification; however, the intrinsic reaction rate (IRR) of coal char conversion at the same O₂ concentration still increases in an orderly manner under O₂/CO₂, O₂/N₂ and O₂/H₂O atmospheres. This result is due to the different chemisorption mechanisms of CO₂ and H₂O, namely, the production of C(CO), C(OH) and C(H) from CO₂ and H₂O chemisorption. At the same O₂ concentration, the trends and magnitudes of variable activation energies for coal char combustion under O₂/CO₂ and O₂/N₂ atmospheres are similar, while they are very different from those under O₂/H₂O conditions. Therefore, CO₂ has little influence on the reactivity, while H₂O changes the reactivity. In addition, according to the developed reaction mechanism, it is concluded that the SVAE method contributes to the characteristic intrinsic reactivity of coal char conversion under different atmospheres.

在O ₂ / H ₂ O气氛下与在O ₂ / CO ₂或O ₂ / N ₂气氛下相比，煤焦转化率的固有反应性差异的原因已通过简单的可变活化能在热重分析仪中进行了研究。 （SVAE）方法结合了吸附/解吸反应机理。结果表明，在非等温实验中仅发生了CO ₂或H ₂ O的化学吸附，而没有发生气化。然而，在O ₂ / CO条件下，相同O ₂浓度下煤焦转化率的本征反应速率（IRR）仍然有序增加。₂，O ₂ / N ₂和O ₂ / H ₂ O的气氛。该结果归因于CO ₂和H ₂ O的不同化学吸附机理，即由CO ₂和H ₂ O的化学吸附产生C（CO），C（OH）和C（H）。在相同的O ₂浓度下，O ₂ / CO ₂和O ₂ / N ₂气氛下煤焦燃烧的可变活化能的趋势和大小是相似的，但与O ₂ / H ₂ O条件下的变化很大。。因此，CO ₂对反应性的影响很小，而H ₂ O会改变反应性。此外，根据开发的反应机理，可以得出结论，SVAE方法有助于在不同气氛下煤焦转化的特征固有反应性。