Treatment of NO and NO₂with a Mg−Al oxide slurry

Abstract

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 Mg-Al oxide slurry. In this study, we examined the ability of a Mg-Al oxide slurry to treat NO and NO(2) gas streams. The Mg-Al oxide slurry only partially removed the NO and NO(2). The ability of Mg-Al oxide to remove NO is based on the adsorption of NO molecules onto the surface of the Mg-Al oxide rather than the formation of an Mg-Al layered double hydroxide (Mg-Al 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 Mg-Al oxide adsorbed NO(-)(2) and NO(-)(3) onto the surface and formed Mg-Al LDH intercalated with NO(-)(2) and NO(-)(3). Based on these results, we conclude that the Mg-Al oxide slurry is an effective treatment for NO(x).