Sulfur oxides are one of the most dangerous atmospheric pollutants since they contribute directly to acid rain formation.Metal oxides derived from hydrotalcites appear to be useful environmental adsorbents for the removal of SOx.A series of layered double hydroxide containing different divalent metals (Mg2+, Ni2+, or Zn2+) were synthesized by urea hydrolysis method with Al3+ as the trivalent metal.All the catalysts lead to formation of mixed oxides when calcined at 773K.They were well characterized by ICP, XRD, SEM, XPS and N2 adsorption/desorption isotherm analyses.The acid-base properties were characterized by pyridine chemisorption and CO2-TPD.The acid-base sites at the surface could determine their ability to retain and transform SO2.The behaviors of SO2 adsorption were studied using in situ FTIR spectroscopy.The results revealed that SO2 was adsorbed to form surface sulfite (SO3 2-), bisulfite (HSO3-), and sulfate (SO42-).Information on the reaction mechanism has also been discussed.