The contribution of free radicals in paracetamol degradation by UV/NaClO

Le Truong Giang, Dao Thi Phuong, Quan Cam Thuy, Dao Hai Yen
Author affiliations


  • Le Truong Giang
  • Dao Thi Phuong
  • Quan Cam Thuy
  • Dao Hai Yen



Paracetamol, UV/Chlorine process, reactive species


UV/Chlorine is an emerging advanced oxidation process which forms several reactive species including OH, Cl, OCl. This study investigated the contribution of three main free radicals: OH, Cl, OCl on Paracetamol degradation under different conditions. Benzoic acid (BA), Nitro benzene (NB) and DMOB were used as probe compounds. The second rate constant of OH, Cl, OCl with PRC were determined: 4.19 (±0.15) ×109 M-1s-1; 3.71 1010 M-1s-1; 3.532×109 M-1s-1, respectively. The formation of free radicals depends on pH. In particular, at pH 5: the contribution of OH and     (-•OCl, Cl) are 45 %, 41 %, respectively, at pH 8.5, the contribution of free radicals increases up to 63 %.

Keywords. Paracetamol, UV/Chlorine process, reactive species.


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How to Cite

Giang, L. T., Phuong, D. T., Thuy, Q. C., & Yen, D. H. (2017). The contribution of free radicals in paracetamol degradation by UV/NaClO. Vietnam Journal of Chemistry, 55(6), 720.