Co/SBA-16 coating supported on a 3D-printed ceramic monolith for peroxymonosulfate-activated degradation of Levofloxacin

Yan Shao; Yifan Yan; Jingshan Wang; Qijie Jin; Haitao Xu; Xueying Zhang

doi:10.1016/j.jcis.2023.03.112

Co/SBA-16 coating supported on a 3D-printed ceramic monolith for peroxymonosulfate-activated degradation of Levofloxacin

J Colloid Interface Sci. 2023 Aug:643:137-150. doi: 10.1016/j.jcis.2023.03.112. Epub 2023 Mar 23.

Authors

Yan Shao¹, Yifan Yan², Jingshan Wang², Qijie Jin³, Haitao Xu⁴, Xueying Zhang⁵

Affiliations

¹ School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China. Electronic address: y.shao@njtech.edu.cn.
² School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China.
³ School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
⁴ School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, China. Electronic address: htxu@njtech.edu.cn.
⁵ School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China. Electronic address: xueyingzhang@163.com.

PMID: 37058889
DOI: 10.1016/j.jcis.2023.03.112

Abstract

This study reports a simple method for anchoring dispersed Co nanoparticles on SBA-16 mesoporous molecular sieve coating grown on the 3D-printed ceramic monolith (i.e., Co@SBA-16/ceramic). The monolithic ceramic carriers with a designable versatile geometric channel could improve the fluid flow and mass transfer but exhibited a smaller surface area and porosity. The SBA-16 mesoporous molecular sieve coating was loaded onto the surface of the monolithic carriers using a simple hydrothermal crystallization strategy, which can increase the surface area of the monolithic carriers and facilitate the loading of active metal sites. In contrast to the conventional impregnation loading method (Co-AG@SBA-16/ceramic), dispersed Co₃O₄ nanoparticles were obtained by directly introducing Co salts into the as-made SBA-16 coating (containing a template), accompanied by conversion of the Co precursor and removal of the template after calcination. These promoted catalysts were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Brunauer-Emmett-Teller theory, and X-ray photoelectron spectroscopy. The developed Co@SBA-16/ceramic catalysts exhibited excellent catalytic performance for the continuous removal of levofloxacin (LVF) in fixed bed reactors. Co/MC@NC-900 catalyst exhibited a ∼ 78% degradation efficiency in 180 min compared to that of Co-AG@SBA-16/ceramic (17%) and Co/ceramic (0.7%). The improved catalytic activity and reusability of Co@SBA-16/ceramic was because of the better dispersion of the active site within the molecular sieve coating. Co@SBA-16/ceramic-1 exhibits much better catalytic activity, reusability and long-term stability than Co-AG@SBA-16/ceramic. After a 720 min continuous reaction, the LVF removal efficiency of Co@SBA-16/ceramic-1 in a 2 cm fixed-bed reactor was stable at 55%. Using chemical quenching experiments, electron paramagnetic resonance spectroscopy, and liquid chromatography-mass spectrometry, the possible LVF degradation mechanism and degradation pathways were proposed. This study provides novel PMS monolithic catalysts for the continuous and efficient degradation of organic pollutants.

Keywords: Co nanoparticles; Levofloxacin; Monolithic catalyst; Peroxymonosulfate; SBA-16 coating.