Treatment of NO and NO ₂ with a MgAl oxide slurry

A selective catalytic reduction process is generally used to treat NO _x; however, this approach results in the leakage of ammonia and requires expensive catalysts. In light of these issues, the specific objective of this study was to develop a new treatment method for a NO _x gas stream with a MgAl oxide slurry. In this study, we examined the ability of a MgAl oxide slurry to treat NO and NO ₂ gas streams. The MgAl oxide slurry only partially removed the NO and NO ₂. The ability of MgAl oxide to remove NO is based on the adsorption of NO molecules onto the surface of the MgAl oxide rather than the formation of an MgAl layered double hydroxide (MgAl LDH) intercalated with NO ^- ₂. NO ₂ removal was greater than NO removal because of the higher solubility of NO ₂. For NO ₂ removal, the MgAl oxide adsorbed NO ^- ₂ and NO ^- ₃ onto the surface and formed MgAl LDH intercalated with NO ^- ₂ and NO ^- ₃. Based on these results, we conclude that the MgAl oxide slurry is an effective treatment for NO _x.