Uesugi Yukino, Nagakawa Haruki, Nagata Morio
Department of Industrial Chemistry, Graduate School of Engineering, Tokyo University of Science, 12-1 Ichigayafunagawara-cho, Shinjuku-ku, Tokyo 162-0826, Japan.
ACS Omega. 2022 Apr 1;7(14):11946-11955. doi: 10.1021/acsomega.1c07294. eCollection 2022 Apr 12.
Hydrogen sulfide (HS) is a highly toxic and corrosive gas that causes a foul odor even at very low concentrations [several parts per billion (ppb)]. However, industrially discharged HS has a concentration range of several tens of ppb to several parts per million (ppm), which conventional methods are unable to process. Therefore, advanced and sustainable methods for treating very low concentrations of HS are urgently needed. TiO-based photocatalysts are eco-friendly and have the ability to treat environmental pollutants, such as low-concentration gases, using light energy. However, there are no reports on HS decomposition or oxidation at concentrations below several ppb. Therefore, in this study, we employed anatase/TiO(B) nanotubes, which have a high specific surface area and an efficient charge-transfer interface, to treat HS. We successfully reduced 10 ppm of HS to 1 ppb or less at a kinetic rate of 75 μmol h g. The suitability of our method was further demonstrated by the generation of sulfate ions and sulfur (as detected by X-ray photoelectron spectroscopy and ion chromatography), which are industrially useful as oxidation products, whereas sulfur dioxide, a harmful substance, was not produced. This is the first study to report HS decomposition down to the ppb level, providing meaningful solutions for malodor problems and potential health hazards associated with HS.
硫化氢（HS）是一种剧毒且具有腐蚀性的气体，即使在极低浓度[十亿分之几（ppb）]时也会产生恶臭。然而，工业排放的HS浓度范围为几十ppb至百万分之几（ppm），传统方法无法处理。因此，迫切需要先进且可持续的方法来处理极低浓度的HS。基于TiO的光催化剂环保，能够利用光能处理环境污染物，如低浓度气体。然而，目前尚无关于浓度低于几ppb的HS分解或氧化的报道。因此，在本研究中，我们采用具有高比表面积和高效电荷转移界面的锐钛矿型/TiO（B）纳米管来处理HS。我们成功地以75 μmol h g的动力学速率将10 ppm的HS还原至1 ppb或更低。通过生成硫酸根离子和硫（通过X射线光电子能谱和离子色谱检测）进一步证明了我们方法的适用性，硫酸根离子和硫作为氧化产物在工业上有用，而未产生有害物质二氧化硫。这是首次报道将HS分解至ppb水平的研究，为与HS相关的恶臭问题和潜在健康危害提供了有意义的解决方案。
