Sulfur- and Nitrogen-Functionalized AlO Materials for Enhanced Arsenic Batch Adsorption.

The adsorption of arsenic in aqueous solutions was successfully achieved by using functionalized AlO materials. This process is important since arsenic in water is extremely toxic to humans and the environment. The adsorbent materials were prepared by functionalizing AlO with sulfur and nitrogen species using different precursors. Several advanced analytical techniques (N adsorption-desorption isotherms at -196 °C, FTIR, TGA, XPS, and pH) were used to characterize the functionalized AlO adsorbents and study the success of the preparation methods. Arsenic adsorption capacity depends on a combination of factors: solution pH, electrostatic interactions, surface modifications, and coexisting substances. The obtained for this study using the Langmuir model was found to be 246 mg/g at pH 3 for AlOfunctionalized with NH. This is due to electrostatic interactions and functional groups at the adsorbent surface. AlO@NH also showed high adsorption capacities for As removal in the real water matrix.