Witkowski Hubert, Jackiewicz-Rek Wioletta, Jarosławski Janusz, Chilmon Karol, Szkop Artur
Faculty of Civil Engineering, Warsaw University of Technology, 00-637 Warsaw, Poland.
Institute of Geophysics, Polish Academy of Sciences, 01-452 Warsaw, Poland.
Materials (Basel). 2022 Aug 26;15(17):5905. doi: 10.3390/ma15175905.
The application of photocatalytic materials has been intensively researched in recent decades. The process of nitric oxide (NO) oxidation during photocatalysis has been observed to result in the formation of nitric dioxide (NO). This is a significant factor of the photocatalysis process, as NO is more toxic than NO. However, it has been reported that ozone (O) is also formed during the photocatalytic reaction. This study analyzed the formation and oxidationof O during the photocatalytic oxidation of NO under ultraviolet irradiation using commercial photocatalytic powders: AEROXIDE TiO P25 by Evonik, KRONOClean 7050 by KRONOS, and KRONOClean 7000 by KRONOS. An NO concentration of 100 ppb was assumed in laboratory tests based on the average nitric oxide concentrations recorded by the monitoring station in Warsaw. A mix flow-type reactor was applied in the study, and the appropriateness of its application was verified using a numerical model. The developed model assumed an empty reactor without a photocatalytic material, as well as a reactor with a photocatalytic material at its bottom to verify the gas flow in the chamber. The analysis of the air purification performance of photocatalytic powders indicated a significant reduction of NO and NO and typical NO formation. However, no significant formation of O was observed. This observation was verified by the oxidation of pure ozone in the process of photocatalysis. The results indicated the oxidation of ozone concentration during the photocatalytic reaction, but self-decomposition of a significant amount of the gas.
近几十年来，光催化材料的应用得到了深入研究。在光催化过程中，一氧化氮（NO）的氧化过程被观察到会导致二氧化氮（NO₂）的形成。这是光催化过程中的一个重要因素，因为NO₂比NO毒性更大。然而，据报道，在光催化反应过程中也会形成臭氧（O₃）。本研究使用商业光催化粉末分析了在紫外线照射下NO光催化氧化过程中O₃的形成和氧化：赢创的AEROXIDE TiO₂ P25、科慕的KRONOClean 7050和科慕的KRONOClean 7000。基于华沙监测站记录的平均一氧化氮浓度，在实验室测试中假定NO浓度为100 ppb。本研究采用了混合流型反应器，并使用数值模型验证了其应用的适用性。所开发的模型假定了一个没有光催化材料的空反应器，以及一个底部装有光催化材料的反应器，以验证室内的气流。对光催化粉末的空气净化性能分析表明，NO和NO₂显著减少，且典型的NO₂形成。然而，未观察到O₃的显著形成。这一观察结果通过光催化过程中纯臭氧的氧化得到了验证。结果表明，在光催化反应过程中臭氧浓度发生了氧化，但大量气体发生了自分解。
