Adsorption kinetics of N2O on natural zeolites

Abstract

The adsorption kinetics of pure N2O on natural zeolites of the erionite (ZAPS), morde- nite (ZNT), and clinoptilolite (ZSL) types has been measured in the temperature range of 0-100 ºC using a glass, high-vacuum volumetric system. The adsorption capacities of N2O on the ZNT and ZSL samples were lower than that on ZAPS. This result can be due to the limiting volume of the micropores of these zeolites and to the quantity of cations available per unit mass of the dehydrated zeolites (cationic density). It was found that the adsorbed amount and the adsorption rate diminish with increasing tem- perature. This behavior allows us to deduce that the adsorption process of N2O is not of the activated type and that it is not influenced by kinetic effects. It was established that the adsorption of N2O on ZAPS can be effected most efficiently at ambient tem- perature, whereas the use of ZSL could be recommended at 100 ºC.