Activation of Peroxymonosulfate by CuO-Supported Attapulgite/Activated Carbon for Organic Contaminant Removal

In this study, the CuO@ATT/AC catalyst was designed and synthesized by a simple process of immersion–doping–calcination to boost the catalytic performance toward peroxymonosulfate (PMS) and remove sulfadiazine (SDZ). The results of optimized preparation experiments indicated that the doping of the materials with AC markedly enhanced the activation of PMS, demonstrating not only superior catalytic performance but also a reduction in the leaching of Cu. The CuO@ATT/AC/PMS system achieved 96.5% SDZ removal within 60 min with only 0.03 mg/L of Cu leaching. In addition, the removal efficiency of SDZ reached above 90% across a wide pH range of 5–9 and operating temperature (25–35 °C). CuO@ATT/AC demonstrated exceptional stability and reusability, achieving a 95% removal rate for SDZ after five cycles. Furthermore, both radical and nonradical species were implicated in the degradation of SDZ. •OH, SO4•–, and 1O2 were identified as the primary reactive species involved in the system. This study presents an environmentally friendly and cost-effective composite catalyst for the degradation and elimination of organic contaminants in water.