School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China.
School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China.
J Colloid Interface Sci. 2023 Aug;643:137-150. doi: 10.1016/j.jcis.2023.03.112. Epub 2023 Mar 23.
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 CoO 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.
本研究报告了一种将分散的 Co 纳米粒子锚定在 3D 打印陶瓷整体式载体上生长的 SBA-16 介孔分子筛涂层上的简单方法（即 Co@SBA-16/ceramic）。具有可设计多功能几何通道的整体式陶瓷载体可以改善流体流动和传质，但表面积和孔隙率较小。介孔分子筛涂层通过简单的水热结晶策略负载在整体式载体的表面上，这可以增加整体式载体的表面积并便于负载活性金属位。与传统的浸渍负载方法（Co-AG@SBA-16/ceramic）相比，通过直接将 Co 盐引入到制成的 SBA-16 涂层（含有模板）中获得分散的 CoO 纳米粒子，随后在煅烧后转化 Co 前体并除去模板。这些促进剂催化剂通过 X 射线衍射、扫描电子显微镜、高分辨率透射电子显微镜、BET 理论和 X 射线光电子能谱进行了表征。开发的 Co@SBA-16/ceramic 催化剂在固定床反应器中对左氧氟沙星（LVF）的连续去除表现出优异的催化性能。与 Co-AG@SBA-16/ceramic（17%）和 Co/ceramic（0.7%）相比，Co/MC@NC-900 催化剂在 180 分钟内表现出约 78%的降解效率。Co@SBA-16/ceramic 催化活性和可重复使用性的提高是由于活性位点在分子筛涂层内的更好分散。与 Co-AG@SBA-16/ceramic 相比，Co@SBA-16/ceramic-1 表现出更好的催化活性、可重复使用性和长期稳定性。在连续反应 720 分钟后，在 2 cm 固定床反应器中，Co@SBA-16/ceramic-1 对 LVF 的去除效率稳定在 55%。通过化学猝灭实验、电子顺磁共振光谱和液相色谱-质谱联用，提出了可能的 LVF 降解机制和降解途径。本研究为有机污染物的连续高效降解提供了新型 PMS 整体式催化剂。
