Electrochemical degradation of the dimethyl phthalate ester on a fluoride-doped Ti/β-PbO2 anode

Chemosphere. 2014 Aug:109:187-94. doi: 10.1016/j.chemosphere.2014.02.018. Epub 2014 Mar 7.

Abstract

The electrooxidation of the dimethyl phthalate (DMP) ester was galvanostatically carried out in a filter-press reactor using a fluoride-doped lead dioxide (β-PbO2,F) film electrodeposited on a Ti substrate. The variables investigated were the nature of the supporting electrolyte (NaCl and Na2SO4), pH (3, 7, and 10), current density (10, 20, 40, 60, and 80mAcm(-2)), and temperature (10, 20, 30, 40, and 50°C). The removal of DMP was monitored through high performance liquid chromatography (HPLC) and total organic carbon (TOC) analysis. The best conditions were obtained using Na2SO4 and at low current densities, independent of the solution pH or temperature. These conditions led to the highest levels of current efficiencies and complete combustion. However, the TOC removal levels were low, due to the generation of highly oxidized intermediates, which was confirmed by the intermediates detected by HPLC.

Keywords: Degradation pathway; Electrochemical oxidation; Lead dioxide; Phthalic acid ester; Recalcitrant intermediates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography, High Pressure Liquid
  • Electrochemical Techniques*
  • Electrodes
  • Electrolytes / chemistry
  • Esters / chemistry
  • Esters / metabolism*
  • Fluorides / chemistry*
  • Hydrogen-Ion Concentration
  • Hydroxyl Radical / chemistry
  • Lead / chemistry*
  • Oxidation-Reduction
  • Oxides / chemistry*
  • Phthalic Acids / analysis
  • Phthalic Acids / chemistry*
  • Sulfates / chemistry
  • Temperature
  • Titanium / chemistry*

Substances

  • Electrolytes
  • Esters
  • Oxides
  • Phthalic Acids
  • Sulfates
  • dimethyl phthalate
  • sodium sulfate
  • Lead
  • Hydroxyl Radical
  • lead oxide
  • Titanium
  • Fluorides