Wet peroxide oxidation process catalyzed by Cu/Al₂O₃: phenol degradation and Cu²⁺ dissolution behavior

Area of Science:

• Environmental Chemistry
• Catalysis
• Water Treatment

Background:

• Catalytic wet peroxide oxidation (CWPO) is crucial for removing organic pollutants in wastewater.
• Copper-based catalysts are significant for CWPO applications.
• Phenol is a common and challenging organic contaminant.

Purpose of the Study:

• To prepare and evaluate two supported copper catalysts (Cu/Al2O3-air and Cu/Al2O3-H2) for phenol degradation via CWPO.
• To investigate the catalytic performance and metal leaching behavior of the prepared catalysts.
• To elucidate the catalytic oxidation mechanism of the Cu/Al2O3-H2 catalyst.

Main Methods:

• Synthesis of Cu/Al2O3-air and Cu/Al2O3-H2 catalysts.
• Catalytic degradation experiments of phenol using CWPO.
• Total organic carbon (TOC) removal rate measurements.
• Metal dissolution analysis.
• Hydroxyl radical quenching experiments.

Main Results:

• Cu/Al2O3-H2 exhibited superior catalytic performance, achieving a 96% TOC removal rate for phenol.
• Cu/Al2O3-H2 showed significantly less metal dissolution compared to Cu/Al2O3-air.
• Increased temperature enhanced organic removal while decreasing metal dissolution.
• Hydroxyl radical quenching experiments supported the proposed catalytic oxidation mechanism.

Conclusions:

• Cu/Al2O3-H2 is a highly effective catalyst for CWPO of phenol with improved stability.
• The study proposes a catalytic oxidation mechanism explaining the catalyst's behavior.
• Findings provide guidance for designing and synthesizing efficient CWPO catalysts for wastewater treatment.