Desalination, Vol.280, No.1-3, 424-427, 2011
Treatment of gaseous hydrochloric acid with magnesium-aluminum oxide using batch operation
We have examined the treatment of gaseous hydrochloric acid (HCl) generated from industrial waste incinerators by using magnesium-aluminum (Mg-Al) oxide obtained from Mg-Al layered double hydroxide (Mg-Al LDH). The HCl removal behaviors with Mg-Al oxide and MgO were found to be similar. HCl removal with Mg-Al oxide increased until 3 h due to the production of MgCl2 by the reaction of HCl with MgO property in the Mg-Al oxide, while it decreased from 3 to 12 h due to the production of Mg-2(OH)(3)Cl with the release of HCl. Further, from 12 to 72 h, the HCl removal progressed due to Mg-Al LDH reconstruction and Mg-2(OH)(3)Cl production. The Mg-Al LDH reconstruction was found to be slower than the MgCl2 production. The reaction of gaseous HCl with the Mg-Al oxide surface is probably easier than its diffusion into Mg-Al oxide. In this study, we have obtained basic data for our proposed treatment method to remove gaseous HCl from incinerated waste in batch reactors. (C) 2011 Elsevier B.V. All rights reserved.