Abstract: “The main aim of this study was the synthesis and characterization of alternative composite inorganic coagulants, resulted from the incorporation of polysilicates and ferric salts in the structure of commonly applied polyaluminum chloride (PACl) in the coagulation–flocculation (C/F) process, in order to increase its efficiency for water and wastewater treatment. The new product is called polyaluminum ferric silicate chloride (PSiFAC) and is synthesized under various experimental conditions and two different preparation methods (copolymerization, or composite polymerization). The major typical properties of the prepared coagulants were examined, i.e. pH, turbidity, conductivity and Al species distribution (e.g. Keggin- Al13), employing the ferron technique. The composition, structure and morphology of the composite coagulants were studied in detail using (among others) the application of FT-IR and SEM techniques. The results show that the new composite materials have high Al13 content (5”

Keywords: composite inorganic coagulants, poly-aluminumferric-silicate-chloride, wastewater treatment