The isosteric heat of adsorption is an important thermodynamic property used to characterize and optimize adsorption processes. In this work, analytic expressions for isosteric heats of adsorption are derived for a collection of commonly used isotherm models and a two‐dimensional molecular equation of state based on the SAFT‐VR approach. The use of these expressions is presented with an example of adsorption of nitrous oxide, N₂O, on biochar, which is a waste biomass charcoal that exhibits high adsorption potential. The results show that accurate fitting of the adsorption isotherms leads to consistent results obtained with different approaches; however, the predicted isosteric heat of adsorption exhibits strong variations in the regions where experimental data is insufficient such in the region of low pressure/low coverage. Convergence on the prediction of the isosteric heat of adsorption by the different models is only observed in the region where no extrapolation of experimental data is needed.

中文翻译：

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吸附等温线模型和二维SAFT-VR状态方程的吸附等规热的解析表达式

吸附的等排热是一种重要的热力学性质，用于表征和优化吸附过程。在这项工作中，基于SAFT-VR方法，收集了一组常用的等温模型和二维分子状态方程，得出了等温吸附热的解析表达式。这些表达式的使用以一氧化二氮N ₂的吸附为例O，在生物炭上，这是一种具有高吸附潜力的废生物质炭。结果表明，吸附等温线的精确拟合导致采用不同方法获得一致的结果。然而，在低压/低覆盖率区域等实验数据不足的区域，预计的等排吸附热表现出很大的变化。仅在不需要外推实验数据的区域中观察到了通过不同模型对等规吸附热的预测的收敛。