Preparation, Characterization And Application Of Polyferric Sulphate

In this paper, research on the preparation of polyferric sulfate in a packing column was conducted. Factors affecting the oxidation rate of ferrous ions and the catalytic index of catalyst, such as reaction temperature, dosage of catalyst, sulfuric acid, oxygen and ferrous concentration, were studied. And the polyferric sulfate product with good quality was obtained. The molecular morphology analysis of the PFS was carried out, and the structure and appearance of the PFS was observed by characterization means of Fourier Transform Infrared Spectroscopy, X-ray Diffraction Analysis, Scanning Electron Microscope as well as Transmission Electron Microscope. Finally, the coagulation performance of the PFS product is investigated. And the results of the research on the preparation of polyferric sulfate with the packed column technology are as follows:1. It is shown that polyferric sulfate could be successfully prepared with the packed column technology. Through the investigation in the affecting factors on the oxidation rate of ferrous ions and the catalytic index of catalyst, such as reaction temperature, dosage of catalyst, sulfuric acid, oxygen and ferrous concentration, the preferred process conditions are as follows: 60℃, catalyst concentration 0.1384g·ml^-1(of which mass fraction is merely 1.1% of the solid ferrous sulfate), n(H₂SO₄):n(FeSO₄·7H2O)= 0.3, oxygen flux 60ml·min^-1 (which is in accordance with the stoichiometnc ratio). Therein the reaction temperature and catalyst concentration are the main influence factors in the whole process. The total reaction time to obtain the final product is 240-300min in the further continuous reaction process.2. The molecular morphology analysis of the PFS is carried out. The structure and appearance of the PFS is observed by characterization means of Fourier Transform Infrared Spectroscopy, X-ray Diffraction Analysis, Scanning Electron Microscope as well as Transmission Electron Microscope. And the result is that the PFS behaves as an amorphous material in general, randomly forming aggregates of various sizes and shapes.3. The prepared PFS product with the packed column technology has very good coagulation performance, and is a kind of excellent flocculant in water treatment. The coagulation efficiency of PFS prepared in this paper in treating kaolin suspension, simulated acid red B wastewater, simulated K₂HPO₄ wastewater as well as the practical coking wastewater is evaluated. And the results show that the PFS has very good coagulation performance.