Removal of SO2 with a Mg-Al oxide slurry via reconstruction of a Mg-Al layered double hydroxide.

Although effective treatments of SO(x) are essential for preventing air pollution, current methods pose other environmental problems such as increased amounts of desulfurized gypsum and reduced landfill lifetimes. We report a process for removing SO(2) from waste streams using a Mg-Al oxide slurry. The ability of the mixed oxide to remove SO(2) increased with slurry quantity and temperature but decreased with time. SO(2) was removed through the reconstruction of a Mg-Al layered double hydroxide (Mg-Al LDH) intercalated with SO(3)(2-), which was derived from the dissociation of H(2)SO(3) upon dissolution of SO(2) in the slurry. SO(2) was not adsorbed onto the surface of the Mg-Al oxide. These results suggest that SO(2) removal using a Mg-Al oxide slurry may be possible without the concomitant problems of conventional treatment methods.
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