Three-dimensional porous chitosan gel microspheres loaded with Ni and La for the treatment of inorganic and organic phosphorus in the water environment

The development of adsorbents with high adsorption capacity and wide adaptable pH range was crucial to effectively controlling of water environment pollution. In this study, three-dimensional porous chitosan gel microspheres loaded with Ni and La (Ni-La-CS) were prepared for the adsorption of excessive phosphorus. The performance was investigated using glyphosate isopropylamine salt (GIS) and KH2PO4, which were selected as representative substances for organic and inorganic phosphorus. Results showed that Ni-La-CS exhibited high phosphorus removal efficiency with wide adaptable pH range. The adsorption process was monomolecular layer chemisorption, and the adsorption was spontaneous and endothermic. The coexistence of F− promoted the adsorption of phosphorus, while Cl−, SO42−, CO32− and HCO3− inhibited the adsorption. The material retained stability even after 5 cycles and the actual phosphorus-containing wastewater with 3.13 mg·L−1 could be treated to meet Chinese first-class standard.