Gamma-Radiolysis of Aqueous Boric Acid Solution

Abstract

The γ-radiolysis of aqueous boric acid solutions of relatively high concentration has been studied. Boric acid significantly promotes hydrogen formation up to 10−7 mol/ml but does not increase oxygen and hydrogen peroxide to any appreciable extent. Since boric acid reacts at a relatively slow rate with species formed by the primary process of water radiolysis, when an effective scavenger for e − aq—the precursor of H2—such as NO− 3 is present, boric acid has no effects upon the total yield of H2 in the range of concentrations studied. However, the yields of other products of the radiolysis—H2O2 and NO− 2—are significantly reduced at high concentrations of boric acid when NO− 3 is present. These results are explained by established reaction schemes for the radiolysis of aqueous solution. Based upon the behavior of NO− 2 from nitrate solutions, it is suggested that NO− 2 reacts with H3BO3 or H2BO3 radicals, the plausible reaction product from the reaction H3BO3+OH →; H2O+H2BO3.