| NUKLEONIKA 2008, 53(Suppl. 1):s31-s37
COMPUTATION OF THE EFFECT OF pH ON SPUR CHEMISTRY IN WATER RADIOLYSIS AT ELEVATED TEMEPRATURESDorota Swiatla-Wojcik Institute of Applied Radiation Chemistry, Technical University of Łódź, 116 Żeromskiego Str., 90-924 Łódź, Poland Diffusion-kinetic model has been employed to calculate the effect of pH and associated ionic strength on the primary yields in the radiolysis of water from ambient temperature to 200°C. Account has been taken of the effect of ionic strength, I, up to 0.1 mol·dm–3 in both acidic and alkaline solutions resulting from the addition of H+ and OH-, assuming the counter ions have unit charge. The primary yields are essentially independent of pH for I =< 10–4. Above I = 10–4 mol·dm–3 the primary yields of e-aq and H2 in acidic solutions decrease whereas the primary yields of the H atom, hydroxyl radical and hydrogen peroxide increase. At I >10–3 mol·dm–3 in alkaline solutions, the OH radical and hydrogen peroxide are partially converted into O•– and HO2– , respectively. Increases in the total yields G•OH + GO•- and Ge–aq + GH• and a decrease in GH2O2 + GHO-2 have been found with increasing pH. At elevated temperatures the effect of pH is diminished. The temperature effect on the primary yields in acidic and alkaline solutions is nearly the same as in neutral water. Close X |