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Different Role of Bisulfite/Sulfite in UVC-S(IV)-O₂ System for Arsenite Oxidation in Water.

ABSTRACT: It is of interest to use UV-sulfite based processes to degrade pollutants in wastewater treatment process. In this work, arsenic (As(III)) has been selected as a target pollutant to verify the efficacy of such a hypothesized process. The results showed that As(III) was quickly oxidized by a UV-sulfite system at neutral or alkaline pH and especially at pH 9.5, which can be mainly attributed to the generated oxysulfur radicals. In laser flash photolysis (LFP) experiments (?_ex = 266 nm), the signals of SO₃^•- and e_aq^- generated by photolysis of sulfite at 266 nm were discerned. Quantum yields for photoionization of HSO₃^- (0.01) and SO₃^2- (0.06) were also measured. It has been established that e_aq^- does not react with SO₃^2-, but reacts with HSO₃^- with a rate constant 8 × 10⁷ M^-1s^-1.

SUBMITTER: Luo T

PROVIDER: S-EPMC6631152 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Different Role of Bisulfite/Sulfite in UVC-S(IV)-O2 System for Arsenite Oxidation in Water.

Luo Tao T Wang Zhenhua Z Wang Yi Y Liu Zizheng Z P Pozdnyakov Ivan I

Molecules (Basel, Switzerland) 20190621 12

It is of interest to use UV-sulfite based processes to degrade pollutants in wastewater treatment process. In this work, arsenic (As(III)) has been selected as a target pollutant to verify the efficacy of such a hypothesized process. The results showed that As(III) was quickly oxidized by a UV-sulfite system at neutral or alkaline pH and especially at pH 9.5, which can be mainly attributed to the generated oxysulfur radicals. In laser flash photolysis (LFP) experiments (λex = 266 nm), ...[more]

PMID: 31234408

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