Adsorption behavior of beryllium(II) on copper-oxide nanoparticles dispersed in water: A model for (7)Be colloid formation in the cooling water for electromagnets at high-energy accelerator facilities.

The adsorption behavior of Be(II) on CuO nanoparticles dispersed in water was studied as a model for colloid formation of radioactive (7)Be nuclides in the cooling water used for electromagnets at high-energy proton accelerator facilities. An aqueous Be(II) solution and commercially available CuO nanoparticles were mixed, and the adsorption of Be(II) on CuO was quantitatively examined. From a detailed analysis of the adsorption data measured as a function of the pH, it was confirmed that Be(II) is adsorbed on the CuO nanoparticles by complex formation with the hydroxyl groups on the CuO surface (>S-OH) according to the following equation: n > S-OH + Be(2+) ⇔ (>S-O)n Be((2-n)+) + nH(+) (n = 2, 3) S : solid surface.