Title | The significance of a second adsorption phase with weakly adsorbed species for the calculation of the surface concentrations of a mixture: methanol-DME and methanol-ethene adsorption in SAPO-34 |
Authors | Wang, Fei Kobayashi, Yasukazu Li, Yuxin Wang, Yao Wang, Dezheng |
Affiliation | Peking Univ, Sch Earth & Space Sci, Key Lab Orogen Belts Crustal Evolut, Beijing 100871, Peoples R China. Tsinghua Univ, Dept Chem Engn, Beijing 100084, Peoples R China. |
Keywords | IAST SAPO-34 zeolite Competitive adsorption Dual-site Langmuir isotherm DIMETHYL ETHER ZEOLITES THERMODYNAMICS CONFINEMENT DIFFUSION CATALYSIS H-ZSM-5 |
Issue Date | 2015 |
Publisher | RESEARCH ON CHEMICAL INTERMEDIATES |
Citation | RESEARCH ON CHEMICAL INTERMEDIATES.Kyoto, JAPAN,2015/12/1,41(9561-9573). |
Abstract | With the calorimetric (adsorption heat versus coverage) curve also measured together with the adsorption isotherm, the simultaneous use of both curves showed that there were two phases of adsorption in the adsorption of methanol, dimethyl ether, ethene and propane in SAPO-34. The dual-site Langmuir equation gave good fits to the adsorption data to support the interpretation that a second (type 2) adsorption phase occurred in the high-pressure region in addition to a first (type 1) adsorption phase on the acid sites at lower pressures. Adsorption experiments and calculations using binary gas mixtures showed that due to the existence of two types of adsorption, the multicomponent Langmuir isotherm equation (Langmuir competitive adsorption model) calculated incorrect surface concentrations when the concentrations were high. In contrast, the ideal adsorbed solution theory (IAST) calculated correct surface concentrations in the adsorption of mixtures. |
URI | http://hdl.handle.net/20.500.11897/435677 |
ISSN | 0922-6168 |
DOI | 10.1007/s11164-015-1981-x |
Indexed | SCI(E) EI CPCI-S(ISTP) |
Appears in Collections: | 地球与空间科学学院 造山带与地壳演化教育部重点实验室 |