Open AccessHeterogeneous uptake of carbonyl sulfide onto kaolinite within a temperature range of 220–330 K
Author(s) -
Liu Yongchun,
Ma Jinzhu,
Liu Chang,
He Hong
Publication year - 2010
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2010jd014778
Subject(s) - kaolinite , desorption , atmospheric temperature range , physisorption , adsorption , analytical chemistry (journal) , activation energy , carbonyl sulfide , chemistry , sulfide , inorganic chemistry , materials science , mineralogy , thermodynamics , environmental chemistry , organic chemistry , physics , sulfur
In this study the heterogeneous uptake of carbonyl sulfide (OCS) onto kaolinite was investigated using a Knudsen cell reactor within the temperature range of 220–330 K. Results showed that OCS could only be adsorbed at Al‐OH sites on kaolinite reversibly within this temperature region. The initial true uptake coefficient was measured to be (1.68 ± 0.12) × 10 −7 at 300 K. It showed no observable dependence on the pressure of OCS, while it varied significantly with temperature, and can be expressed as γ t = exp(1293/ T − 20.0)/[1 + exp(1293/T − 20.0]. The values of Δ H obs and Δ S obs during the adsorption process were −10.7 ± 1.1 kJ mol −1 and −166.3 ± 4.5 J K −1 mol −1 , respectively. The activation energy for desorption of OCS on kaolinite was 19.5 ± 1.1 kJ mol −1 . The uptake of OCS by kaolinite owing to reversible physisorption may have little influence on the sink of OCS in the atmosphere.