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

摘要

Mg-Al layered double hydroxide intercalated with NO_3~- and Mg-Al oxide were found to remove hazardous materials such as B and As, as well as Cl~- and So_4~(2-), from artificial and real hot spring wastewater. However, compared with the mixture of Al_2(SO_4)_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 PO_4~(3-) from artificial semiconductor plant wastewater. Both adsorbents have the same ability to remove B from landfill wastewater as the mixture of Al_2(SO_4)_3 and Ca(OH)_2; furthermore, both remove Cl~-, Br~-, and So_4~(2-). The benefit of Mg-Al layered double hydroxide intercalated with NO_3~- 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 NO_3~- is the most suitable adsorbent for the treatment of hot spring and landfill wastewater.