Study on structural characterization and algae-removing efficiency of polymeric aluminum ferric sulfate (PAFS)

Abstract Polymeric aluminum ferric sulfate (PAFS), as a novel inorganic coagulant, was prepared through direct oxidation process using industrial by-product ferrous sulfate heptahydrate (FeSO4·7H2O) and industrial aluminum oxide (Al2O3 content of 16%) as the main materials. PAFS was characterized by Fourier transformed infrared spectrophotometer, scanning electron microscopy, and X-ray diffraction. The coagulation mechanism and molecular conformation of PAFS were analyzed and the different conditions of flocculation effect were investigated in the paper. In order to test the coagulating performances of PAFS, traditional coagulants such as polymeric ferric sulfate, polymeric aluminum chloride, and polymeric aluminum ferric chloride were used to carry out the comparison tests on algae removal efficiency. The results show the removal efficiency for turbidity and chlorophyll a using PAFS were 92.8 and 95.3%, respectively, which were higher than those of the traditional coagulants.