Fluorine, as one of the indispensable trace elements in the human body, plays an important role in the formation of bones and teeth. However, excessive intake of fluoride can cause a series of diseases such as fluorosis, fluorosis, and decreased hemoglobin levels, affecting human health. With the large-scale discharge of fluorine-containing industrial wastewater in modern industrial production processes, the fluoride content in surface water continues to increase. To ensure ecological balance and human health, it is imperative to solve the problem of fluoride pollution in water bodies.

The commonly used methods for fluoride removal in industry include chemical precipitation, ion exchange, adsorption, etc. Among them, adsorption is widely used due to its advantages of simple operation, high fluoride removal efficiency, low cost, and environmental friendliness. It utilizes a chemical reaction between fluoride ions and adsorbent materials to fix fluoride ions in the pores of the adsorbent material, achieving selective adsorption of fluoride ions and achieving the goal of fluoride removal. It is easy to see from this principle that the key to adsorption and fluoride removal technology lies in the selection of adsorption materials. Not only does it require strong affinity with fluoride ions, but it also requires a large specific surface area and pore volume, rich surface active sites, to achieve high adsorption capacity. Under these requirements, activated alumina with an unstable cubic spinel structure has become the preferred adsorbent for fluoride removal.