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 3h 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 12h due to the production of Mg2(OH)3Cl with the release of HCl. Further, from 12 to 72h, the HCl removal progressed due to Mg-Al LDH reconstruction and Mg2(OH)3Cl 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.
- Gaseous hydrochloric acid
- Mg-Al layered double hydroxide
- Mg-Al oxide