Nguyen Thanh X, Bhatia Suresh K, Nicholson David
Division of Chemical Engineering, University of Queensland, Brisbane, Queensland 4072, Australia.
Langmuir. 2005 Mar 29;21(7):3187-97. doi: 10.1021/la047545h.
In this paper, we present the results of the prediction of the high-pressure adsorption equilibrium of supercritical gases (Ar, N2, CH4, and CO2) on various activated carbons (BPL, PCB, and Norit R1 extra) at various temperatures using a density-functional-theory-based finite wall thickness (FWT) model. Pore size distribution results of the carbons are taken from our recent previous work,(1,2) using this approach for characterization. To validate the model, isotherms calculated from the density functional theory (DFT) approach are comprehensively verified against those determined by grand canonical Monte Carlo (GCMC) simulation, before the theoretical adsorption isotherms of these investigated carbons calculated by the model are compared with the experimental adsorption measurements of the carbons. We illustrate the accuracy and consistency of the FWT model for the prediction of adsorption isotherms of the all investigated gases. The pore network connectivity problem occurring in the examined carbons is also discussed, and on the basis of the success of the predictions assuming a similar pore size distribution for accessible and inaccessible regions, it is suggested that this is largely related to the disordered nature of the carbon.
在本文中,我们展示了使用基于密度泛函理论的有限壁厚(FWT)模型,对超临界气体(氩气、氮气、甲烷和二氧化碳)在不同温度下于各种活性炭(BPL、PCB和Norit R1特级)上的高压吸附平衡进行预测的结果。这些活性炭的孔径分布结果取自我们最近的前期工作,采用这种方法进行表征。为了验证该模型,在将模型计算得到的这些被研究活性炭的理论吸附等温线与其实验吸附测量结果进行比较之前,先将由密度泛函理论(DFT)方法计算得到的等温线与通过巨正则蒙特卡罗(GCMC)模拟确定的等温线进行全面验证。我们阐述了FWT模型在预测所有被研究气体吸附等温线方面的准确性和一致性。还讨论了在所研究的活性炭中出现的孔网络连通性问题,并且基于在假设可及区域和不可及区域具有相似孔径分布的情况下预测成功这一点表明,这在很大程度上与碳的无序性质有关。