Anchoring N and Co species on the aluminum-graphite surface to enhance oxygen activation for the degradation of tetracycline at neutral conditions

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-09, Vol.496, p.154168, Article 154168
• Main Authors: Da, Yufeng, Zou, Yanxue, Zhou, Aijuan, Wei, Yuman, Dong, Guijun, Wu, Xiaochun, Wang, Jingwen, Liu, Yong
• Format: Article
• Language: English
• Subjects: Advanced oxidation process; Aluminum-graphite; Oxygen activation; Tetracycline
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.154168

[Display omitted] •Anchoring N and Co species on the aluminum-graphite surface was implemented.•N and Co species promoted the Fenton-like reactivity of Al-Gr-N/Co.•HO•, O2•− and 1O2 can be generated by Al-Gr-N/Co in air purging water.•Efficient degradation of tetracycline was achieved at neutral pH conditions. Molecular oxygen (O2) activation for reactive species (RSs) production has recently received increasing interest. Reported herein is a novel O2 activator (Al-Gr-N/Co), synthesized by anchoring N and Co species on the aluminum-graphite (Al-Gr) surface, that could achieve efficient degradation of tetracycline (TC) by activating O2 in air purging water. RSs, including HO•, O2•− and 1O2, could be generated in the Al-Gr-N/Co/Air process, achieving 97.8 % of TC degradation at pH 7. This degraded TC can be attributed to the oxidation by 1O2 and HO•; direct adsorption by Al-Gr-N/Co also contributed to the TC degradation. The N species promoted the H2O2 production during O2 activation by Al-Gr-N/Co; these produced H2O2 could be further converted to RSs by Co and N species. Demethylation, hydroxylation and dehydration reactions were proposed as the oxidation pathways of TC by Al-Gr-N/Co/Air. TOC result suggests that TC and the oxidized intermediates could be adsorbed by Al-Gr-N/Co or converted to inorganic compounds. Negligible amount of the dissolved metal ions (82.2 %) in lake water, tap water and MBR secondary effluents suggested that the Al-Gr-N/Co/Air process could be potentially applied in real water systems.