Fluoride removal performance of highly porous activated alumina

Activated alumina (AA) is promising for fluoride removal but is limited by conventional production methods. This study synthesized porous AA using a sol–gel method, supercritical drying, and calcination. The enhanced AA demonstrated higher fluoride adsorption capacities, due to its increased porosity and surface area, outperforming traditionally produced AA. Adsorption processes involved both chemical and physical mechanisms.