This research explored the feasibility of preparing and utilizing preformed polymeric solution of Al(III) and Fe(IB) as coagulants for water treatment. The differentiation and quantification of hydrolytic Al and Fe species in the coagulants were done by utilizing spectrophotometric method based on the interaction of Al or Fe with ferron as a complexing agent. In addition, Al-27-NMR, FT-IR, and powdered XRD were used to characterize the nature and structure of the hydrolytic species in these coagulants. The properties of the polyaluminum chloride (PACl) and polymeric iron chloride (PICl) showed that the mass fractions of the maximum polymeric Al produced at r(OH/Al)=2.2 and Fe at r = 1.5(OH/Fe) were 85% and 20% of the total aluminum and iron in solution, respectively. Coagulation tests were conducted under various coagulant dosages and pHs for each coagulant prepared. In case of PACl coagulants, a coagulation test on Nakdong river waters with three PACls (r=2.0, 2.2, 2.35) showed that the effectiveness of coagulation was in the order, r=2.2>2.0>2.35, corresponding to the order of polymeric aluminum contents. And, for the PICl coagulants, the PICl of r=1.5 was most effective for the removal of turbidity and TOC from the raw water.

Water Treatment Polymeric Coagulants Hydrolytic Species Coagulation Tests

Akitt JW, Farthing A, J. Magn. Reson., 32, 345 (1978)
Akitt JW, Greenwood NN, Khandelwal BL, J. Chem. Soc.-Dalton Trans., 1226 (1972)
Akitt JW, Greenwood NN, Khandelwal BL, Lester GD, J. Chem. Soc.-Dalton Trans., 604 (1972)
APHA-AWWA-WEF, "Standard Methods for the Examination of Water and Wastewater," APHA AWWA WEF., 20th eds. (1988)
Bersillon J, Hsu P, Fiessinger F, J. Soil. Sci. Soc. Am., 44, 3 (1980)
Bottero JY, Cases JM, Fiessinger F, Poirer JE, J. Phys. Chem., 84, 2933 (1980) 
David R, Parker DR, Environ. Sci. Technol., 26(5), 908 (1992) 
Hur JM, Kim SH, Korean J. Chem. Eng., 17(4), 433 (2000)
Murphy PJ, Posner AM, Quirk JP, Aust. J. Soil Res., 13, 189 (1975) 
Oh MH, So JH, Lee JD, Yang SM, Korean J. Chem. Eng., 16(4), 532 (1999)
Park KY, Lee K, Kim J, HWAHAK KONGHAK, 32(5), 742 (1994)
Schneider W, Schwyn B, "The Hydrolysis of Iron in Synthetic, Biological, and Aquatic Media," Aquatic Surface Chemistry (Stumm, W. eds.), John Wiley and Sons, N.Y. (1990)
Schwyn B, "Die Hydrolyse von Eisen(III) β-Eisenoxyhydroxid: Vonder Keimbildung bis zur Koagulation," Ph.D. Dissertation No. 7404, ETH, Zurich, Switzerland (1983)
Smith RM, "Relation Among Equilibrium and Nonequilibrium Aqueous Species of Aluminum Hydroxy Complexes," Nonequilibrium Systems in Natural Water Chemistry (Gould, R.F. eds.), A.C.S. Advances in Chemistry Series No. 106, Washington, D.C., 250 (1971)