Contrasting radical activity

Reaction intermediates formed during the ultra-violet (UV) activation of hydrogen peroxide (H2O2) (UV-AHP) and persulfate (S2O82-) (UV-APS) include hydroxyl (•OH) and sulfate radicals (SO4•-), respectively. These radicals, used in oxidation treatment systems to degrade a broad spectrum of environmental contaminants, may also react with non-target chemical species (scavengers) that limit treatment efficiency. UV-AHP and UV-APS treatment systems were amended with solid phase alumina to assess scavenging by solid surfaces. The relative rates of reaction between the target compound, rhodamine B dye (RhB), and aqueous and solid phase scavengers was used to assess treatment performance. The overall rate of reaction and rate of radical scavenging was greater for •OH than SO4•-. Scavenging by dissolved constituents was dominated by the oxidant used (H2O2, S2O82-); and the rate of radical scavenging by alumina was greater than the rate of RhB oxidation in all cases. Treatment efficiency was lower in the UV-AHP than in the UV-APS treatment system and was attributed to greater aqueous and solid phase scavenging rates. The cost of commercially available H2O2 ($0.031 mol-1) and PS ($0.24 mol-1) was used in conjunction with the overall treatment efficiency to assess specific cost of treatment. The specific cost to treat the probe compound with UV-AHP was greater than UV-APS and was attributed to the much lower treatment efficiency with UV-AHP. The much-desired high reaction rate constants between •OH and environmental contaminants, relative to SO4•-, comes at the cost of greater combined scavenging rates, and consequently lower treatment efficiency. This dataset is associated with the following publication: Rusevova Crincoli, K., and S.G. Huling. Contrasting hydrogen peroxide- and persulfate-driven oxidation systems: Impact of radical scavenging on treatment efficiency and cost. Chemical Engineering Journal. Elsevier BV, AMSTERDAM, NETHERLANDS, 404: 1-6, (2021).

                                            [
  "020:00"
]
                                        

                                            {
  "fn": "Scott Huling",
  "hasEmail": "mailto:huling.scott@epa.gov"
}
                                        

                                            [
  {
    "title": "Science Hub_data set message.xlsx",
    "mediaType": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
    "downloadURL": "https://pasteur.epa.gov/uploads/10.23719/1518483/Science%20Hub_data%20set%20message.xlsx"
  }
]
                                        

                                            [
  "Hydroxyl Radicals",
  "Mineral Surfaces",
  "Scavenging",
  "Sulfate Radicals",
  "kinetics",
  "treatment efficiency"
]
                                        

                                            [
  "020:097"
]
                                        

                                            {
  "name": "U.S. EPA Office of Research and Development (ORD)",
  "subOrganizationOf": {
    "name": "U.S. Environmental Protection Agency",
    "subOrganizationOf": {
      "name": "U.S. Government"
    }
  }
}
                                        

                                            [
  "https://doi.org/10.1016/j.cej.2020.126404"
]
                                        

                                            null