Anodic oxidation of benzoquinone using diamond anode

Area of Science:

• Environmental Chemistry
• Electrochemistry
• Pollutant Degradation

Background:

• 1,4-benzoquinone (BQ) is a highly toxic xenobiotic compound.
• Effective methods for BQ degradation are crucial for environmental protection.

Purpose of the Study:

• To investigate the anodic degradation of 1,4-benzoquinone (BQ) using electrochemical oxidation.
• To evaluate the efficiency of a boron-doped diamond anode for BQ mineralization.

Main Methods:

• Electrochemical oxidation in a single-compartment flow cell under galvanostatic conditions.
• Varied parameters included applied current (0.5-2 A), BQ concentration (1-2 g dm(-3)), temperature (20-45 °C), and flow rate (100-300 dm(3) h(-1)).
• Monitoring of BQ decay, intermediates, and mineralization using HPLC and COD measurements.

Main Results:

• The boron-doped diamond anode achieved total mineralization of BQ under all tested conditions.
• BQ removal followed pseudo-first-order kinetics, with rate constants increasing with current density.
• Chemical oxygen demand (COD) removal was enhanced by higher current and flow rates, with minimal temperature effect.

Conclusions:

• Electrochemical oxidation with a boron-doped diamond anode is a highly effective method for the complete mineralization of 1,4-benzoquinone.
• The process relies on electrogenerated hydroxyl radicals for pollutant degradation.
• Optimizing current density and flow rate can improve the efficiency of BQ removal.