Wang Shengli, Jia Yanping, Song Lianfa, Zhang Haifeng
School of Chemistry Engineering, Northeast Electric Power University, Jilin 132012, Jilin, P. R. China.
Department of Civil, Environmental, and Construction Engineering, Texas Tech University, Lubbock, Texas 79409-1023, United States.
ACS Omega. 2018 Dec 27;3(12):18456-18465. doi: 10.1021/acsomega.8b02149. eCollection 2018 Dec 31.
Hydroxylamine (HA) can react with hydrogen peroxide (HO) to generate hydroxyl radical (HO), but the reaction rate between them is very slow (2.2 × 10 M s). We propose a new system to accelerate the formation of aminoxyl radical (NHO) by the addition of cerium [Ce(IV)] to induce the continuous production of HO through reaction with HO. We also investigate the decolorization and mineralization of rhodamine B (RhB) and mechanism in the Ce(IV)/HO/HA system. The initial pH plays a significant role in decolorization of RhB. In this work, observation of the rapid decolorization process after 60 min revealed that approximately 80% of RhB was degraded at the initial pH of 4.0. The HO radicals were considered as the primary reactive oxidant in the system, during its investigation through coumarin capturing, benzoic acid capturing, and radical quenching experiments. The results of the present study suggest that the addition of Ce(IV) can greatly enhance the production of HO, and the rapid decolorization and mineralization of RhB can occur through the Ce(IV)/HO/HA system at acidic pH conditions.
羟胺（HA）可与过氧化氢（HO）反应生成羟基自由基（HO），但它们之间的反应速率非常缓慢（2.2×10 M s）。我们提出了一种新体系，通过添加铈[Ce(IV)]来加速氨氧自由基（NHO）的形成，铈[Ce(IV)]通过与HO反应诱导HO的持续产生。我们还研究了铈（IV）/HO/HA体系中罗丹明B（RhB）的脱色和矿化及其机制。初始pH值对RhB的脱色起着重要作用。在这项工作中，60分钟后对快速脱色过程的观察表明，在初始pH值为4.0时，约80%的RhB被降解。在通过香豆素捕获、苯甲酸捕获和自由基猝灭实验对该体系进行研究期间，HO自由基被认为是体系中的主要活性氧化剂。本研究结果表明，添加Ce(IV)可大大提高HO的产生量，并且在酸性pH条件下，通过Ce(IV)/HO/HA体系可实现RhB的快速脱色和矿化。
