Key Laboratory of Environmental Materials and Pollution Control, The Education Department of Jilin Province, Jilin Normal University, Siping, China; College of Environmental Science and Engineering, Jilin Normal University, Siping, Jilin, China.
J Hazard Mater. 2020 Jan 5;381:120910. doi: 10.1016/j.jhazmat.2019.120910. Epub 2019 Jul 19.
Congo red (CR) is a kind of refractory contaminant. Conventional biological treatment processes are ineffective for the CR degradation. However, photocatalysis technology could be an alternative for the decomposition of CR because of its high efficiency. In this study, we prepared three kinds of photocatalysts, all of which have advanced visible light excitation characteristics. The magnetic catalyst C-TiO@FeO/AC was produced by loading C-TiO and nano-FeO onto granular activated carbon (AC). C-TiO@FeO/AC has a band gap of 2.535 eV, stable magnetic characteristics, and stability toward CR removal. C-TiO@FeO/AC showed the best performance for CR removal under both simulated sunlight (200-800 nm) and visible light (400-800 nm) irradiation compared to the other catalysts. The CR removal rate reached 92.9% after 30 min of simulated sunlight irradiation, and the reaction rate constant was 0.1776 min. Under visible light, the CR removal rate reached 65%. The hydroxyl radical (OH) was detected, and its concentration was determined. Furthermore, the spectral analysis results indicated that the azo bonds and aromatic rings in CR were destroyed. The C-TiO@FeO/AC has a self-cleaning ability to prevent organic contamination. This study provides a new way of thinking and a simple preparation technique for magnetic visible light catalyst synthesis.
刚果红（CR）是一种难处理的污染物。传统的生物处理工艺对 CR 的降解无效。然而，光催化技术可以作为 CR 分解的替代方法，因为它具有高效性。在这项研究中，我们制备了三种光催化剂，它们都具有先进的可见光激发特性。磁性催化剂 C-TiO@FeO/AC 通过将 C-TiO 和纳米 FeO 负载到颗粒活性炭（AC）上制备而成。C-TiO@FeO/AC 的带隙为 2.535 eV，具有稳定的磁性和对 CR 去除的稳定性。与其他催化剂相比，C-TiO@FeO/AC 在模拟阳光（200-800nm）和可见光（400-800nm）照射下对 CR 去除表现出最佳性能。在模拟阳光照射 30 分钟后，CR 的去除率达到 92.9%，反应速率常数为 0.1776 min。在可见光下，CR 的去除率达到 65%。检测到了羟基自由基（OH），并测定了其浓度。此外，光谱分析结果表明，CR 中的偶氮键和芳环被破坏。C-TiO@FeO/AC 具有自清洁能力，可防止有机污染。本研究为磁性可见光催化剂的合成提供了一种新的思路和简单的制备技术。
