Hydrothermal synthesis of easy-recycled tobermorite/SiO_2/Fe_3O_4 composites for efficient treatment of phosphorus in wastewater

摘要

In this work, tobermorite/SiO_2/Fe_3O_4 composites were designed and synthesized by hydrothermal method for the treatment of phosphorus in wastewater. The composites were characterized by scanning electron microscopy and X-ray diffraction. The removal efficiency of phosphorus on the tobermorite/SiO_2/Fe_3O_4 composites was carried out and investigated under various conditions, such as contact time, sorbent content, and pH. After the multi-run experiments, the phosphorous elimination of the tobermorite/SiO_2/Fe_3O_4 composites was declined slightly comparing with the first-run experiments. Compared with the conventional crystallization methods, tobermorite/SiO_2/Fe_3O_4 composites not only gave high efficiency to remove phosphorus from wastewater without any complicated pretreatment, but also provided excellent magnetic properties for separating the phosphorus from water, which made it easy recycled. Moreover, tobermorite/SiO_2/Fe_3O_4 composites had excellent P-elimination properties even in the strong acidic or basic conditions. Therefore, tobermorite/SiO_2/Fe_3O_4 composites were important candidate for water quality control and protection.