Radiation-induced reduction of chromium(VI)(Cr(VI) by ?酌-irradiation was studied with an initial concentration of 42 mg/L in aqueous solutions. Sever al factors which might affect the reduction of Cr(VI) to Cr(III) were examined. pH of aqueous solution aff- ects the reduction efficiency significantly. Acidic condition of aqueous solution accelerates the process. At pH 2, a reduction of 8 6.2% was achieved with the absorbed dose of 15 kGy, while, with the same dose, a t pH 5 and 7, the reduction of Cr(VI) were only 36.3% and 22.2%, respectively. E thanol(0.1% in V:V) and sodium carbonate(1 mmol/L) were added into the solution respectively as relatively non-toxic hydroxyl radical scavengers. Reduction rate increased greatly in the presence of ethanol at each pH. Reduction efficiency o f Cr(VI) was enhanced in neutral condition with the addition of sodium carbonate , however, no enhancement was found in acidic condition. The reduction of Cr(VI ) was restrained when the solution was saturated with oxygen; however, the restr aint was not significant.
