Adsorption Study of Methane on Activated Meso-carbon Microbeads by Density Functional Theory

• 作 者: 邵晓红 黄世萍 沈志刚 陈建峰
• 机 构: College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China,Co
• 出 处: Chinese Journal of Chemistry
• 发表日期: 2004年02期
• 关键词: Adsorption methane isotherm desorption Figure hysteresis gravimetric shaped cond

A combined method of density functional theory (DFT) and statistics integral equation (SIE) for the determina-tion of the pore size distribution (PSD) is developed based on the experimental adsorption data of nitrogen on acti-vated mesocarbon microbead (AMCMB) at 77 K. The pores of AMCMB are described as slit-shaped with PSD. Based on the PSD, methane adsorption and phase behavior are studied by the DFT method. Both nitrogen and methane molecules are modeled as Lennard-Jones spherical molecules, and the well-known Steeles 10-4-3 poten-tial is used to represent the interaction between the fluid molecule and the solid wall. In order to test the combined method and the PSD model, the Intelligent Gravimetric Analyzer (IGA-003) was used to measure the adsorption of methane on the AMCMB. The DFT results are in good agreement with the experimental data. Based on these facts, we predict the adsorption amount of methane, which can reach 32.3 w at 299 K and 4 MPa. The results indicate that the AMCMBs are a good candidate for adsorptive storage of methane and natural gas. In addition, the capillary condensation and hysteresis phenomenon of methane are also observed at 74.05 K.

A combined method of density functional theory (DFT) and statistics integral equation (SIE) for the determina-tion of the pore size distribution (PSD) is developed based on the experimental adsorption data of nitrogen on acti-vated mesocarbon microbead (AMCMB) at 77 K. The pores of AMCMB are described as slit-shaped with PSD. Based on the PSD, methane adsorption and phase behavior are studied by the DFT method. Both nitrogen and methane molecules are modeled as Lennard-Jones spherical molecules, and the well -known Steeles 10-4-3 poten-tial is used to represent the interaction between the fluid molecule and the solid wall. In order to test the combined method and the PSD model, the Intelligent Gravimetric Analyzer (IGA-003) was used to The results of the adsorption of methane on the AMCMB. The DFT results are in good agreement with the experimental data. Based on these facts, we predict the amount of methane of which 32.3 w at 299 K and 4 MPa. the A MCMBs are a good candidate for adsorptive storage of methane and natural gas. In addition, the capillary condensation and hysteresis phenomenon of methane are also observed at 74.05 K.