Removal of boron and fluoride in wastewater using Mg-Al layered double hydroxide and Mg-Al oxide

- NO3·Mg-Al LDH and Mg-Al oxide can remove B from different types of wastewater.
- The NO3·Mg-Al LDH does not require neutralization after treatment.
- The NO3·Mg-Al LDH is the most suitable adsorbent.

Mg-Al layered double hydroxide intercalated with NO3− and Mg-Al oxide were found to remove hazardous materials such as B and As, as well as Cl− and SO42−, from artificial and real hot spring wastewater. However, compared with the mixture of Al2(SO4)3 and Ca(OH)2, both adsorbents were inferior for the removal of B from real hot spring wastewater. Both adsorbents were also found to remove F− and PO43− from artificial semiconductor plant wastewater. Both adsorbents have the same ability to remove B from landfill wastewater as the mixture of Al2(SO4)3 and Ca(OH)2; furthermore, both remove Cl−, Br−, and SO42−. The benefit of Mg-Al layered double hydroxide intercalated with NO3− is that it does not require neutralization after the treatment. Overall, it can be stated that among the materials tested, Mg-Al layered double hydroxide intercalated with NO3− is the most suitable adsorbent for the treatment of hot spring and landfill wastewater.