Preparation of Fe(III) Peeling‐Intercalation Ball Clay/Oyster Shell Composites and Phosphorus Removal from Wastewater

Abstract

AbstractFe(III) is introduced into ball clay by the peeling‐intercalation technique, and mixed with oyster shell (B‐FB‐OS), pelletized, and calcined to form granular materials (FB‐OS) demonstrated that the presence of SiO2 and Fe(III) is favorable for CaCO3 pyrolysis, and the pyrolysis temperature of CaCO3 in B‐FB‐OS is 46 °C lower than that of oyster shell. A large amount of flocculent products are generated on the surface of FB‐OS after phosphorus removal, but pore channels are still observed. EDS analysis and theoretical analysis show that the flocculent products contain Ca3(PO4)2, suggesting the occurrence of chemisorption. Fe3+/Ca2+ has synergism, the maximum adsorption capacity of FB‐OS is 244.65 mg g−1, and the phosphorus concentration after treatment is lower than 1 mg L−1. The kinetic adsorption behavior of FB‐OS is applicable to Pseudo‐second‐order rate equation. The results of the Weber–Morris model demonstrate that the adsorption process is controlled by outer film diffusion and intraparticle diffusion together. The thermodynamic behavior of FB‐OS is consistent with the Freundlich isotherm model (R2 = 0.945). The comprehensive analysis indicates that FB‐OS is multilayer adsorption and nonuniform surface adsorption, and has a strong phosphorus removal ability.