کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5369755 | 1388451 | 2007 | 5 صفحه PDF | دانلود رایگان |
Adsorption kinetics on energetically heterogeneous surfaces under isothermal conditions is analyzed using the uniform energy distribution model. Considering the quasi-equilibrium of surface diffusion between the adsorption sites with different energy, the kinetic equations dÎ/dt=(kapâAdKdiff)(1âÎ) for first-order adsorption and dÎ/dt=kap(1âÎ)2âAdKdiffÎ(1âÎ) for dissociative adsorption are obtained, where Kdiff is a coefficient describing the surface diffusion equilibrium, which depends on the coverage and the energy distribution. Under isochoric conditions with p decreasing due to adsorption, surface diffusion accelerates the rate towards equilibrium significantly, as observed in static calorimetric adsorption experiments. An approximate solution in Lagergren form is derived for this condition.
Journal: Applied Surface Science - Volume 253, Issue 13, 30 April 2007, Pages 5851-5855