Nitrogen-doped oxidized activated carbon as efficient metal-free bifunctional material for bisphenol removal: A tuning of surface chemistry

作者：Wang, Xiaobo^*; Zhu, Wenjun; Wang, Nan; Zuo, Xiaohua^*

来源：Journal of Environmental Chemical Engineering, 2022, 10(6): 108509.

DOI：10.1016/j.jece.2022.108509

• Nitrogen-doped
• Activated carbon
• Adsorption
• Catalytic oxidation
• Persulfate

Nitrogen modified oxidized activated carbon (N-OAC) was prepared by nitric acid oxidation and ammonia hydrothermal treatment of activated carbon. The surface functional groups of AC were changed by controlling the synthetic conditions and characterized. It was found that oxygen and nitrogen functional groups was introduced on the surface of AC. The deeper degree of oxidation was in favour of N doping. With well-suited amount of oxygen and nitrogen modification, the adsorption and activation ability toward persulfate could be enhanced simultaneously. The adsorption experiment showed that the maximum adsorption capacity (q(m)) of N-OAC for bisphenol A (BPA) obtained from a Langmuir isotherm was 147 mg g(-1) at 298 K, which was about 1.23 and 1.5 times than that of AC (121 mg g(-1)) and N-free-OAC (108 mg g(-1)). N-OAC could also activate persulfate, producing strong oxidizing sulfate radicals. The apparent degradation rate constant of BPA on N-OAC was 0.039 min(-1), being about 39 times than that (0.001 min(-1)) on AC. After adsorption equilibrium within 120 min, the use of N-OAC (240 mg L-1) and persulfate (4 mmol L-1) almost completely removed the added bisphenols (60 mg L-1) at pH 6.6 within 60 min. A synergistic effect and correlation between the adsorption ability, catalytic performance and chemical structures of N-OAC was discussed.

• 单位
  华中科技大学