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In this study, boron removal from aqueous solutions was examined using Dowex 2×8 anion exchange resin. The sorption behaviour of resin was investigated as a function of pH, contact-time and temperature, initial boron concentration of solution, resin dosage and effect of other ions. The maximum sorption value for boron was observed at pH 9. The percent removal of boron decreased as temperature and initial boron concentration increased. The presence of other ions in solutions affected the sorption of boron significantly. The Langmuir isotherm was used to describe observed sorption phenomena. The maximum sorption capacity of Dowex 2×8 was determined as 16.98 mg B/g at pH 9 and 25EC. The quantitative stripping of boron from resin was obtained with 0.5 M H2SO4 or 0.5 M HCl solutions at 25EC. A generalised ion exchange kinetic model was applied to fit the kinetic data obtained by using the Dowex 2×8 and the rate-determining step is determined as film-intraparticle diffusion.

The use of the Dowex 2×8 for boron removal from aqueous solutions was investigated. The following results are obtained: C Maximum boron removal was obtained at pH 9. C Initially, the rate of sorption of boron onto the Dowex 2×8 was very high. This was then followed by a slower rate, and gradually approached a plateau. The sorption of boron decreased as temperature increased. C The amount of boron sorbed increased with increasing initial boron concentration. C The empirical Langmuir isotherm was found to adequately describe the equilibrium relation [1] R.O. Nable, G.S. Banvelos and J.G. Paull, Boron toxicity, Plant and Soil, 198 (1997) 181–198. [2] F.H. Nielsen, Boron in human and animal nutrition, Plant and Soil, 193 (1997) 199–208. [3] O. Okay, H. Güçlü, E. Soner and T. Balkaş, Boron pollution in the Simav River, Turkey and various methods of boron removal, Water Res., 19 (1985) 857–862. [4] S. Goldberg, Reanalysis of boron adsorption on soils and soil minerals using the constant capacitance model, Soil Sci. Soc. Am. J., 63 (1999) 823–829. [5] H. Polat, A. Vengosh, I. Pankratov and M. Polat, A new methodology for removal of boron from water by coal and fly ash, Desalination, 164 (2004) 173– 188. [6] N. Öztürk and D. Kavak, Adsorption of boron from