College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, China.
College of Chemistry and Life Sciences, Chifeng University, Chifeng 024000, China.
J Phys Chem B. 2021 Aug 5;125(30):8494-8501. doi: 10.1021/acs.jpcb.1c03378. Epub 2021 Jul 23.
The Bohart-Adams model was one of the most widely used breakthrough models in column experiments. However, it usually provided a poor fit for the modeling of an asymmetric breakthrough curve. This work proposed the -order Bohart-Adams and fractal-like Bohart-Adams models. The former indicated a nonlinear decay process of the concentration of the adsorbate or residual capacity of the adsorbent, while the latter reflected a diffusion-limited process on the heterogeneous surfaces. The Bohart-Adams and modified Bohart-Adams models were mathematically equivalent. The applicability of the -order Bohart-Adams and fractal-like Bohart-Adams models was validated by norfloxacin and Cu(II) adsorption in a fixed-bed column. Compared with the Bohart-Adams model, the two new models had better fitting performance with higher and lower χ values, and all of the residuals were randomly distributed. The fractal-like Bohart-Adams and modified dose-response models provided the best fitting quality for the adsorption of Cu(II) ( = 0.9956 and χ = 7.56 × 10) and norfloxacin ( = 0.9991 and χ = 1.37 × 10), respectively. This work may provide a practical method for the modeling of the asymmetric breakthrough curves.
Bohart-Adams 模型是柱实验中应用最广泛的突破模型之一。然而，它通常对非对称突破曲线的建模拟合效果较差。本工作提出了 -阶 Bohart-Adams 模型和类分形 Bohart-Adams 模型。前者表明吸附质浓度或吸附剂残余容量的非线性衰减过程，而后者则反映了非均相表面上的扩散受限过程。Bohart-Adams 和修正 Bohart-Adams 模型在数学上是等效的。通过在固定床柱中吸附诺氟沙星和 Cu(II)验证了 -阶 Bohart-Adams 模型和类分形 Bohart-Adams 模型的适用性。与 Bohart-Adams 模型相比，这两个新模型的拟合性能更好，具有更高的 和更低的 χ 值，并且所有残差均随机分布。类分形 Bohart-Adams 和修正剂量反应模型分别为 Cu(II)（ = 0.9956 和 χ = 7.56×10）和诺氟沙星（ = 0.9991 和 χ = 1.37×10）的吸附提供了最佳的拟合质量。本工作可能为非对称突破曲线的建模提供了一种实用方法。
