气体透过碳膜的非平衡动力学模拟研究

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气体透过碳膜的非平衡动力学模拟研究

王淑梅; 于养信; 高光华

State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2006-04-28 发布日期:2006-04-28
通讯作者: 王淑梅

Non-equilibrium Molecular Dynamics Simulation on Pure Gas
Permeability Through Carbon Membranes

WANG Shumei; YU Yangxin; GAO Guanghua

State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

Received:1900-01-01 Revised:1900-01-01 Online:2006-04-28 Published:2006-04-28
Contact: WANG Shumei

摘要/Abstract

摘要： The permeation of various pure gas (H2, He, Ne, CH4 and Ar) through carbon membranes is investigated using a dual control volume grand canonical molecular dynamics method. A two-dimensional slit pore is employed instead of the one-dimensional pore. Compared with the experiments, simulation results show that the improvement of pore model is very necessary. The effects of membrane thickness, pore width and temperature on gas permeance and ideal separation factor are also discussed. Results show that gas permeates through membrane according to Knudsen diffusion in large pore, while Knudsen diffusion is accompanied by molecular sieving in small pore. Moreover, methane is easily adsorbed on the membrane surface due to strong attractive interactions of membrane and shows higher permeance than that of Knudsen flow. In addition, it is noted that when membrane thickness is thin enough the permeance of gas does not decrease with the increase of membrane thickness due to the strong adsorption until membrane resistance becomes dominant.

关键词: gas separation;carbon membrane;molecular simulation;flux;permeance

Abstract: The permeation of various pure gas (H2, He, Ne, CH4 and Ar) through carbon membranes is investigated using a dual control volume grand canonical molecular dynamics method. A two-dimensional slit pore is employed instead of the one-dimensional pore. Compared with the experiments, simulation results show that the improvement of pore model is very necessary. The effects of membrane thickness, pore width and temperature on gas permeance and ideal separation factor are also discussed. Results show that gas permeates through membrane according to Knudsen diffusion in large pore, while Knudsen diffusion is accompanied by molecular sieving in small pore. Moreover, methane is easily adsorbed on the membrane surface due to strong attractive interactions of membrane and shows higher permeance than that of Knudsen flow. In addition, it is noted that when membrane thickness is thin enough the permeance of gas does not decrease with the increase of membrane thickness due to the strong adsorption until membrane resistance becomes dominant.

Key words: gas separation, carbon membrane, molecular simulation, flux, permeance

王淑梅, 于养信, 高光华. 气体透过碳膜的非平衡动力学模拟研究
[J]. CIESC Journal.

WANG Shumei, YU Yangxin, GAO Guanghua. Non-equilibrium Molecular Dynamics Simulation on Pure Gas
Permeability Through Carbon Membranes
[J]. .

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气体透过碳膜的非平衡动力学模拟研究

Non-equilibrium Molecular Dynamics Simulation on Pure Gas
Permeability Through Carbon Membranes

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气体透过碳膜的非平衡动力学模拟研究

Non-equilibrium Molecular Dynamics Simulation on Pure Gas Permeability Through Carbon Membranes

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Non-equilibrium Molecular Dynamics Simulation on Pure Gas
Permeability Through Carbon Membranes