Preparation of solid composite polyferric sulfate and its flocculation behavior for wastewater containing high concentration organic compounds

Abstract

A new kind of inorganic polymer flocculant, the solid composite polyferric sulfate (SPFS) was prepared using ferrous sulfate and Na-Bentonite. The obtained SPFS was characterized by FT-IR spectra, thermogravimetric analysis (TG), scanning electron microscope (SEM) and X-ray Diffraction (XRD). It showed that SPFS was a kind of composite inorganic polymer, which was the complex of PFS and Na-Bent, not only a simple mixture of raw materials. The synthetic mechanism and surface structure of SPFS were also discussed. Acting as a kind of environment-friendly flocculating agent, the solid composite polyferric sulfate (SPFS) was applied in pretreatment of potato starch industry wastewater, a typical wastewater containing high concentration organic compounds, which COD was above 6,000 mg/L. The results showed that the COD removal value reached 4,070 mg/L with COD removal rates being 46.6%. Based on these results, it is suggested that the SPFS can be attractive pretreatment agent for the starch industry wastewater.

Isolation, identification, and characterization of an Aspergillus niger bioflocculant-producing strain using potato starch wastewater as nutrilite and its application

“…[ 7 , 8 ]. Although many inorganic and organic synthetic flocculants[ 9 ] have shown good flocculation property, environmental and health problems caused by these flocculants cannot be ignored [ 10 ]. Considering the carcinogenicity and biological incompatibility of the conventional inorganic and organic flocculants, the emerging bioflocculant attracts great interest currently because they are harmless, biodegradable and without the problem of producing secondary pollution to the environment [ 11 ].…”