林产化学与工业2016，Vol.36Issue(2)：79-86,8.DOI:10.3969/j.issn.0253-2417.2016.02.012
改进的密度泛函理论在活性炭孔径分布的应用
Application of Modified Density Functional Theory in Pore Size Distribution Model of Activated Carbon
摘要
Abstract
To improve the accuracy of Pore Size Distribution ( PSD) for activated carbon, we adopt 4 kinds of Density Functional Theory ( DFT) with different methods to calculate excess Helmholtz free energy. The excess adsorption of 3 kinds of gases ( CH4 , N2 and CO2 ) in slit pore with the pore size in the range from 0. 65 to 5 nm was obtained using the pressure of 0. 2-2 MPa at 298 K. The results of methods are similar for CH4 and N2 , but for CO2 , the results of MF and FMSA are underestimated comparing with the results of two DFT methods based on Weight Density Approximation. This means that correlation effect shall not be neglected in the excess Helmholtz free energy. WDA ( Yu) with the smallest condition number of the kernel is more suitable for PSD study. Moreover, 6 numerical methods are used to fit 3 kinds of isotherms of 3 activated carbon samples with the average deviation between the fitting result and experiment data less than 5 %, and the required PSD models can be used to compare qualitatively for different samples.关键词
经典密度泛函理论应用/平均场近似法改进/多孔材料/吸附积分方程/孔径分布Key words
application of classical density functional theory/modifications of mean field approximation/porous materials/adsorption integral equation/pore size distribution分类
化学化工引用本文复制引用
王国栋,蒋剑春,孙康..改进的密度泛函理论在活性炭孔径分布的应用[J].林产化学与工业,2016,36(2):79-86,8.基金项目
“十二五”国家科技支撑计划资助(2015BAD21B05) （2015BAD21B05）
林业公益性行业科研专项(201404610) （201404610）
中国林科院林业新技术所基本科研业务费专项资金(CAFINT2013C02) （CAFINT2013C02）
