Abstract
Amphetamine-type stimulants are among the most prevalent and widespread commonly abused drugs. Amphetamine and its derivatives were detected in aquatic environment. This study aimed to demonstrate experimentally the ability of gamma-irradiation combined with persulfate anions (S2O82-) to degrade and mineralize the amphetamine in aqueous solution. An initial amphetamine concentration of 125 mu M in distilled water was completely degraded by a gamma-ray dose of 2.8 kGy. Generation of the sulfate radical (SO4 center dot-) from the fast reaction of added S2O82- with hydrated electrons (e(aq)(-); k(eaq)(/S2O82-)(-) = 1.1 x 10(10) M-1 S-1) improved the efficiency of amphetamine degradation and mineralization. A gamma-ray dose of 0.667 and 0.350 kGy in the absence and presence of S2O82- anions degraded 90% of the amphetamine, respectively. For gamma-ray/free O-2 and gamma-ray/S2O82- systems, 11.5 and 7 kGy was required for 50% amphetamine mineralization, respectively. Addition of HCO3- anions lowered the amphetamine degradation yield, whereas N-2 gas, SO42-, and cl(-) anions had a negligible effect.