Degradation of sulfamerazine by a novel CuxO@C composite derived from Cu-MOFs under air aeration

Most metal-organic frameworks (MOFs) are synthesized from carboxylate and metal precursors by hydrothermal process, which will consume a large amount of solvent and carboxylate. To address this issue, a new strategy for Cu-based MOFs was developed, in which the Cu-based MOFs was obtained by using abundant natural polymer (tannic acid) as one of the precursors and using high-energy ball milling to achieve a self-assembly of tannic acid and copper sulfate. Based on this strategy, a novel Cu-based MOFs derivative (Cu x O@C composite) was synthesized by high-temperature sintering of Cu-based MOFs and used for sulfamerazine (SMR) removal via O 2 activation. The BET specific surface area and average pore size of Cu x O@C composite were 110.34 m 2  g −1 and 21.06 nm, respectively, which made Cu x O@C composite had the maximum adsorption capacity ( Q max ) for SMR of 104.65 mg g −1 and favored the subsequent degradation of SMR. The results from XRD and XPS indicated that Cu x O@C composite contained a lot of Cu 0 and Cu 2 O with the sizes of 76.6 nm and 9.8 nm, respectively, which led to its high performance of O 2 activation. The removal efficiency of SMR and 90.2% TOC achieved 100% and 90.2%, respectively in the Cu x O@C/air system at initial pH of 4.0, air flow rate of 100 mL min −1 , Cu x O@C dosage of 1 g L −1 and reaction time of 30 min. Reactive species, including H 2 O 2 , OH and O 2 - radicals were detected in the Cu x O@C/air system, and OH and O 2 - were mainly responsible for the degradation of SMR.