The effect of the UV photon flux on the photoelectrocatalytic degradation of endocrine-disrupting alkylphenolic chemicals

Environ Sci Pollut Res Int. 2016 Oct;23(19):19237-45. doi: 10.1007/s11356-016-7121-3. Epub 2016 Jun 30.

Abstract

The photoelectrocatalytic (PEC) degradation of 4-nonylphenol ethoxylate (NP4EO) using a low, moderate, or high UV photon flux in different treatment times was investigated. The byproducts were verified using gas chromatography with flame ionization detection (GC-FID) and gas chromatography with quadrupole mass analyzer (GC-qMS). The GC results showed that the use of a low (2.89 μmol m(-2)s(-1)) or a high (36.16 μmol m(-2)s(-1)) UV photon flux reaching the anode surface was associated to the production of alcohols and the toxic byproduct nonylphenol (NP), leading to the same degradation pathway. Meanwhile, the use of a moderate UV photon flux (14.19 μmol m(-2)s(-1)) reaching the anode surface did not produce alcohols or the NP toxic byproduct. This study demonstrates that different UV photon fluxes will have an influence in the degradation of NP4EO with or without generation of toxic byproducts. Furthermore, it is concluded that, after the determination of the UV photon flux able to degrade NP4EO without NP formation, the treatment time is essential in removal of NP4EO, since increasing the treatment time of 4 to 10 h, when using the PEC best conditions (moderate UV photon flux), implies in a higher treatment efficiency.

Keywords: Advanced oxidation process; Byproduct; Endocrine disruptor chemical; Nonylphenol ethoxylate; Photoelectrocatalytic degradation; UV photon flux.

MeSH terms

  • Electrolysis
  • Endocrine Disruptors / chemistry*
  • Endocrine Disruptors / radiation effects
  • Flame Ionization
  • Gas Chromatography-Mass Spectrometry
  • Phenols / chemistry*
  • Phenols / radiation effects
  • Photolysis
  • Photons*
  • Time Factors
  • Ultraviolet Rays*
  • Waste Disposal, Fluid / methods*
  • Water Pollutants, Chemical / chemistry*
  • Water Pollutants, Chemical / radiation effects

Substances

  • Endocrine Disruptors
  • Phenols
  • Water Pollutants, Chemical