Copper hydroxyl sulfate as a heterogeneous catalyst for the catalytic wet peroxide oxidation of phenol

Abstract

Copper hydroxyl sulfates Cu₄(OH)₆SO₄-A and Cu₄(OH)₆SO₄-B were successfully synthesized by a simple hydrothermal method and applied as heterogeneous catalysts to degrade phenol wastewater in a batch reactor in the presence of hydrogen peroxide (H₂O₂). The influence of temperature, H₂O₂ dosage, initial pH and catalyst dosage on phenol and COD removal efficiencies was investigated to get optimum conditions and to understand the degradation process more clearly. The Cu²⁺ concentrations in the solutions after three hours of reaction were also measured to prove the catalysts were stable. Excellent results, phenol removal efficiency of 99% and COD removal efficiency of 97%, were achieved when treating 100 and 500 mg L⁻¹ phenol wastewater. Even though the catalysts had low specific surface area, mesopores mainly existed to decrease diffusion control of H₂O₂ and organics.