Hydrothermal synthesis of lanthanum oxide nanoparticles modified pumice: High lanthanum oxide loading ratio and efficiency phosphate removal

Abstract

Efficient and less restrictive phosphorus pollution treatment methods are required to treat water eutrophication. Lanthanum oxide nanoparticles modified pumice (LOMP) with a high loading ratio was prepared by a simple hydrothermal synthesis method which adjusted the synthesis conditions. The XRD, SEM, and TEM results show that the lanthanum oxide nanoparticles have successfully modified on the surface of the pumice, forming a disordered hierarchical structure. The adsorption kinetics results showed that phosphate adsorption was more consistent with the pseudo-second-order model. The adsorption isotherm was more consistent with the Sips model, and the theoretical adsorption capacity was 82.77 mg P/L. The results of the effects of the initial pH and the coexisting anions indicate that LOMP has a good phosphate removal efficiency in a wide range of pH and a strong ability to resist the competition of anions. The superior phosphate adsorption performance can be ascribed to the ligand exchange, which also can be promote by hydrogen ions.