Selectivity for CO2 over CH4 on a functionalized periodic mesoporous phenylene-silica explained by transition state theory

authors	Kunkel, C; Vines, F; Lourenco, MAO; Ferreira, P; Gomes, JRB; Illas, F
nationality	International
journal	CHEMICAL PHYSICS LETTERS
author keywords	Periodic mesoporous organosilicas; PMO; CO2/CH4 separation; Transition state theory; DFT
keywords	PRESSURE SWING ADSORPTION; CARBON-DIOXIDE; LANDFILL GAS; ACTIVATED CARBON; POROUS MATERIALS; ORGANIC GROUPS; SEPARATION; ZEOLITE; METHANE; DESORPTION
abstract	Efficient separation of CO2/CH4 is critical in biogas upgrading, requiring highly selective adsorbents. Based on the adsorption energies of 0.30 and 0.14 eV, previously calculated by dispersion corrected density functional theory for adsorption/desorption of CO2 and CH4 on the functionalized periodic mesoporous phenylene-silica material APTMS@Ph-PMO, respectively, transition state theory rates were derived and used to simulate the adsorption/desorption rates of these two gases on APTMS@Ph-PMO. The latter yielded an estimation of initial CO2/CH4 selectivity at various temperatures. At T= 298 K, selectivity of 32.2 agrees to an experimental value of 26.1, which validates the method used for evaluating CO2/CH4 adsorption selectivities. 2017 Elsevier B.V. All rights reserved.
publisher	ELSEVIER SCIENCE BV
issn	Sep-14
isbn	1873-4448
year published	2017
volume	671
beginning page	161
ending page	164
digital object identifier (doi)	10.1016/j.cplett.2017.01.033
web of science category	Chemistry, Physical; Physics, Atomic, Molecular & Chemical
subject category	Chemistry; Physics
unique article identifier	WOS:000395219000026