Nonlinear frequency response method for estimation of single solute adsorption isotherms. Part I: Theoretical basis and simulations
Nonlinear frequency response method for estimation of single solute adsorption isotherms. Part I: Theoretical basis and simulations
复制标题
用于估计单一溶质吸附等温线的非线性频率响应方法。
DOI：
10.1016/j.ces.2007.05.004
复制
发表时间：
2007
影响因子：
4.7
通讯作者：
A. Seidel
中科院分区：
文献类型：
--
作者：
M. Ilic;M. Petkovska;A. Seidel
从理论上提出了一种基于色谱柱非线性频率响应（FR）分析的单溶质吸附等温线测定方法。为了验证该方法，模拟了色谱柱在几个稳态浓度附近的周期性入口浓度变化（正弦波形）的FR。从入口和出口浓度变化计算了三阶频率响应函数（FRFs），并使用快速傅立叶变换进行了分析。之后，吸附等温线的系数估计从低频渐近线的FRF及其衍生物。所获得的系数比较以及用于模拟。本文还讨论了在实验数据分析中可能影响该方法精度的一些因素，如速度波动、噪声和分析数据集大小等的影响。
A method for determination of single solute adsorption isotherms based on the analysis of the nonlinear frequency response (FR) of a chromatographic column is developed theoretically. In order to demonstrate this method, the FR of a chromatographic column is simulated for the periodical inlet concentration changes (sine waveform) around several steady-state concentrations. The frequency response functions (FRFs) up to the third order are calculated from the inlet and outlet concentration changes, which are analysed using the fast Fourier transform. Afterwards the coefficients of an adsorption isotherm are estimated from the low-frequency asymptotes of the FRFs and their derivatives. The obtained coefficients compare well with those used for simulations. Also discussed are some aspects that might affect the accuracy of the suggested method when it is applied to the analysis of experimental data, e.g. influence of velocity fluctuations, noise and size of the analysed data set.