Poly Ferric Silicate Sulphate (PFSiS): Characterization, Coagulation Behavior and Applications in Oily Wastewater Treatment

A new kind of polymer inorganic coagulant-PFSiS (Poly Ferric Silicate Sulphate) coagulants, at different Fe/Si molar ratios and
B
values (
B
=OH/Fe) were prepared. Then, the turbidity removal efficiency of PFSiS in treating kaolin suspension was investigated. The results showed that turbidity was removed highly by using PFSiS under the certain conditions. Moreover, FTIR analysis indicated that Si participated hydrolytic process of Fe(III). Oil and COD removal efficiency of PFSiS in treating oily wastewater were also evaluated. Under the optimum conditions, oil removal efficiency in the range of 95-97% and more than 60% of COD was removed. Additionally, the PFSiS coagulants exhibited a better coagulation performance than polymer inorganic coagulant, i.e. PFS (Poly Ferric Sulphate).