Defluoridation investigation of Yttrium by laminated Y-Zr-Al tri-metal nanocomposite and analysis of the fluoride sorption mechanism.

In this study, a laminated nanocomposite of Y-Zr-Al with significantly high surface area of 256.6 m2 /g was successfully prepared, and was used to investigate the defluoridation performance of sorbent based on Yttrium. The composite showed high fluoride sorption performance, especially at low F- concentration conditions. SEM, BET, Elemental Mapping and XPS were used to characterize physicochemical properties of the composite in detail. Several influence factors including pH, presence of coexisting anions and contacting time were detailly investigated. The sorption course was studied by equilibrium sorption isotherm and sorption kinetics. Based on experimental results, a mechanism for fluoride sorption onto Y-Zr-Al composite was proposed, which revealed that there were three main sorption models, including mesoporous diffusion sorption, electronic interaction sorption and ion exchange, in the sorption course. The composite was considered to be highly potential in treating fluoride polluted waste water due to its high efficiency, high anti-interference ability and easy operation, and the discovery of fluoride highly attractive rare earth element was important to further understand and develop defluoridation sorbents based on rare earth.