Nitrogen-doped mesoporous carbon material (NCMK-3) as a catalyst for the removal of 4-chlorophenol during persulfate oxidation and its efficiency after reuse

ABSTRACT

Persulfate (PS) oxidation of 4-chlorophenol (4CP) is mostly catalysed by relatively expensive metal substrates. In this study, we investigated the influence of nitrogen-doped and non-doped mesoporous carbon materials (NCMK-3 and CMK-3) during persulfate (PS) oxidation of 4CP in water. Batch experiments were conducted such that PS was added to simulated contaminant mixture after 1 h agitation with NCMK-3 and CMK-3. Further, the experiment was carried out at different temperatures, pH ranges, concentrations of persulfate (PS), and different doses of NCMK-3, since it recorded better removal rates compared to CMK-3. The results revealed that NCMK-3 and CMK-3 aided the removal of 4CP from water during persulfate oxidation. When persulfate was added after an hour of equilibration with CMK-3 and NCMK-3, 83% and 92% of 4CP were removed within 20 min, respectively, whereas lower removal rates (≤40) were recorded in the absence of persulfate (PS). The removal rates of 4CP increased with an increase in temperature but reduced in the alkaline medium in the NCMK-3/PS system. The efficiency of the NCMK-3 reduced significantly after it was reused three times. Based on the results, NCMK-3 influences the activity of PS oxidation of 4-chlorophenol (4CP) and exhibited a synergistic effect in the removal of the organic contaminant from water.

GRAPHICAL ABSTRACT

KEYWORDS:

• Mesoporous carbon material
• persulfate oxidation
• 4-chlorophenol
• N-doped
• catalysis

Acknowledgments

The authors are grateful for the financial supports from the National Natural Science Foundation grant (No. 41572217), National Water Pollution Control and Treatment Science and Technology Major Project (No. 2018ZX07109-003) of China.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Natural Science Foundation of China [grant number 41572217]; National Water Pollution Control and Treatment Science and Technology Major Project of China [grant number 2018ZX07109-003].