Ion exchange synthesis of copper-based hydroxyapatite for the catalytic degradation of phenol

Abstract

Hydroxyapatite (HAP) is a material renowned for its exceptional capabilities in adsorbing and exchanging heavy metal ions, making it a widely employed substance within the environmental domain. This study aims to present a novel material, namely copper–HAP (Cu–HAP), which was synthesized via an ion exchange method. The resulting material underwent comprehensive characterization using scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and Brunauer–Emmett–Teller (BET) analysis. Subsequently, based on the principle of the Fenton-like oxidation reaction, the material was used for the degradation of phenol. The outcomes of the investigation revealed that the optimal preparation conditions for the catalyst were achieved at a temperature of 40 °C, a pH value of 5, and a relative dosage of Cu–HAP at 100 mg/g. Under the reaction conditions of a catalyst dosage of 2 g/L, a 30% hydrogen peroxide concentration of 30 mM, a phenol concentration of 20 mg/L, a pH value of 6, a temperature of 40 °C, and the degradation rate of phenol impressively reached 98.12%. Furthermore, the degradation rate remained at 42.31% even after five consecutive cycles, indicating the promising potential of Cu–HAP in the treatment of recalcitrant organic compounds within this field. HIGHLIGHTS A novel copper-based catalyst (Cu–HAP) has been synthesized and utilized for the catalytic degradation of phenol.; Cu–HAP improved the efficiency of H2O2 in the traditional Fenton reaction.; Cu–HAP surface has a rich pore structure.; The phenol removal rate can still reach 42.31% after five times of reuse.;

Keywords

• catalyst
• fenton-like oxidation
• hydroxyapatite
• ion exchange
• phenol
• water treatment