| Abstract
| - A combination of grand canonical Monte Carlo and molecular dynamics methods has been used toinvestigate the adsorption and diffusion of carbon dioxide confined in seven slit carbon pores from 0.744to 3.72 nm from subcritical to supercritical conditions. Adsorption isotherms and microstructures of carbondioxide molecules in slit carbon pores are analyzed. The effects of pore size and operating conditions onthe parallel and perpendicular diffusion coefficients are examined. The diffusion coefficients of CO2 moleculesconfined in a slit pore in supercritical conditions strongly depend on the pore fluid density. The paralleldiffusion coefficients are on the magnitude of 10-9m2·s-1, a typical liquidlike value. For the pores of reducedwidth larger than 4.0, the parallel diffusion coefficients are generally 10−20 times greater than theperpendicular ones. When the pressure is in the range 2−10 MPa, the parallel diffusion coefficients arein the range (1.3−2.8) × 10-9 m2·s-1 at 323 K, while they are (2.0−5.3) × 10-9 m2·s-1 at 348 K. Diffusioncoefficients parallel and normal to the walls at supercritical temperatures are both 5−15 times larger thanthose at subcritical temperatures.
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