UV/H2O2 oxidation of arsenic and terbuthylazine in drinking water

The aimof this work was to investigate the effectiveness
of ultraviolet (UV) radiation alone and in combination
with hydrogen peroxide for the oxidation of arsenic and
terbuthylazine (TBA). The experimental tests were
performed in groundwater at the laboratory scale
(0.1 mg L−1 As(III) and 10 μg L−1 TBA). Hydrogen
peroxide alone (15 mg L−1) was ineffective on both
arsenic and TBA oxidation; the 253.7-nm radiation
alone did not oxidize arsenic(III), but photolyzed efficiently
TBA (52 % removal yield at a UV dose of 1,200 mJ cm−2). The UV/H2O2 advanced oxidation
(UV dose 600–2,000 mJ cm−2, 5–15 mg L−1 H2O2)
was the most effective process for the oxidation of both
arsenic and TBA, with observed oxidation efficiencies
of 85 and 94 %, respectively, with 5 mg L−1 H2O2 and a
UV dose of 2,000 mJ cm−2.