Multiscale Modeling of Barium Sulfate Formation from BaO

Abstract

The present paper presents a multiscale (DFT to mean-field) modeling approach for describing barium sulfate formation through the adsorption of sulfur oxides on BaO. Sulfur oxide emissions, a major environmental concern, also represent one of the technological issues for a large-scale implementation of alkaline-earth oxides as NO<i>x</i> abatement techniques for vehicle exhaust depollution. SO<i>x</i> adsorption was studied at the atomic level on various BaO sites (terraces, surface defects, and bulk) for a closer description of a real storage material. Ab initio data were used to conceive a kinetic model for SO<i>x</i> adsorption that allows us to follow species adsorption and desorption dynamics. Our results confirm that sulfur oxides interact strongly with the NO<i>x</i> trapping material to form thermodynamically favored sulfate species, consequently leading to the blockage of NO<i>x</i> sorption sites and altering the storage properties