Interactions of SOF2 with molecular sieve 13X

Interactions between the SOF₂ species and molecular sieve type 13X were studied in a SF₆ gas matrix. Adsorption experiments were performed through single or sequential exposures of pre-humidified and virgin dry samples using gas mixtures prepared at concentration levels varying from 1×10⁴ to 5×10 ⁴ ppm_v. In all cases, the initial total pressure was set at 2 bar abs at 298 K. Based on the results, the 13X was found to adsorb the SOF₂ and to transform a portion of it into SO ₂. This hydrolysis reaction led to an increasing amount of SO ₂ in the gas phase which was monitored throughout the experiments, The kinetics observed in the early stage of initial exposure suggested an adsorption process controlled by a concentration gradient. The results also revealed that CO₂ species can be displaced by the SOF₂. When an amount of water as high as 4×10³ ppm_v was initially present in the gas phase, the SOF₂/SO₂ dynamics were not significantly modified. However, the new contaminant was found to be as effectively removed by the sieve as the SOF₂ species. On the other hand, a sieve which had been pre-humidified through extensive exposure to the ambient air released water when subjected to an SOF₂ gas mixture, pointing to a preferential SOF₂ adsorption. Considerations based on the material properties were used to explain the overall phenomena observed