Enhanced Adsorptive Removal Of Fluoride Using Mesoporous AluminaBy Grace Lee, Chao Chen, Seung-Tae Yang, Wha-Seung Ahn

Two different kinds of mesoporous alumina samples were prepared using aluminum tri-sec-butoxide in the presence of either cetyltrimethylammonium bromide (MA-1) or stearic acid (MA-2) as a structure- directing agent, and tested for adsorptive removal of fluoride in water. Both materials contain a worm- hole-like mesopore structure, but exhibited different textural properties: surface area (421 or 650 m2 and pore volume (0.96 or 0.59 cm3 adsorption capacity and faster kinetics to those of the commercial activated aluminas in fluoride removal by adsorption process. MA-2 prepared using stearic acid, in particular, demonstrated an adsorption capacity (14.26 mg/g) and initial adsorption rate (14.6 mg/g min) that were respectively 2.2 and 45 times higher than those of a commercial gamma alumina. The textural features of larger surface area and relatively smaller pore size in MA-2 compared to the activated aluminas are believed to be responsible for this enhancement in adsorption process. /g). These mesoporous aluminas demonstrated significantly improved