Removal of Phosphorus from Wastewater by Different Morphological Alumina

In this work, an organic-free method was used to synthesize different morphological boehmite by controlling the crystallization temperature, and alumina adsorbents were obtained by baking the boehmites at 500 °C. The alumina adsorbents were characterized by X-ray diffraction (XRD), High resolution transmission electron microscope (HRTEM), Fourier transform infrared (FT-IR), N₂ adsorption/desorption analysis, and their phosphorus adsorption properties were comparatively investigated by a series of experiments. The results showed that the self-prepared alumina adsorbents were lamellar and fibrous material, while the industrial adsorbent was a granular material. The lamellar alumina adsorbents had the largest specific surface area and showed better phosphorus adsorption capacity. The maximum adsorption capacity could reach up to 588.2 mg·g^-1; and only 0.8 g·L^-1 of lamellar alumina adsorbent is needed to treat 100 mg·L^-1 phosphorus solution under the Chinese level 1 discharge standard (0.5 mg·L^-1). Further investigation suggests that the lamellar alumina adsorbent kept high adsorption capacity in various solution environments.