Poly Ferric Sulfate (pfs) Appearance: Yellow powder Fe(3+): >20%;Basicity%: 9.0-14.0% Insoluble material%: <0.5% Poly Ferric Sulfate (pfs) PFS is an inorganic high molecular flocculant, is widely suitable for industrial sewage, such as metallurgy, pottery, coal dressing, papermaking, printing and dye, the leather, and petrochemical industry, etc, extensively, the sewage purification of urban life ...