EDDS强化Fe0-Al0体系降解废水中4-氯酚的性能和机理

采用乙二胺二琥珀酸（EDDS）强化Fe⁰-Al⁰体系还原水溶液中的O₂产生H₂O₂和·OH等活性氧（ROS）的绿色高级氧化工艺，以4-氯酚（4-CP）模拟废水为研究对象，考察了溶液的初始pH值、铁铝的质量比、EDDS投加量和4-CP的初始浓度等因素对4-CP降解的影响.采用电子自旋共振（ESR）法、苯甲酸捕捉法以及4-CP的降解产物等证实了ROS的产生及4-CP的降解机制.结果表明：EDDS强化Fe⁰-Al⁰/O₂体系对4-CP的去除率随溶液初始pH的升高而降低，但在pH=2.5～9范围内，始终具有较好的4-CP去除率；随Fe⁰：Al⁰质量比增加4-CP的去除率先增大后减小，最佳质量比为4：1；随EDDS投加量和4-CP初始浓度增加，4-CP的去除率增大；EDDS可使体系的高级氧化能力提高9倍，在初始pH=2.5、Fe⁰=8g/L、Al⁰=2g/L、EDDS=1.5mmol/L条件下，反应3h后100mg/L 4-CP的去除率和脱氯率均达到近100%..

Enhanced bimetallic Fe0-Al0/O2 system by EDDS for degradation of aqueous 4-CP

The green advanced oxidation process of Fe⁰-Al⁰/O₂ enhanced by ethylenediamine disuccinic acid (EDDS) was applied to generating reactive oxygen species (ROS) of H₂O₂ and ·OH by the O₂ spontaneous reduction at normal temperature and pressure. The simulated 4-CP wastewater was degraded in this study. The effects of the initial pH, the mass ratio of Fe⁰ to Al⁰, the EDDS dosage and initial 4-CP concentration were investigated in the process. The insitu -generation of H₂O₂ and ·OH as well as the oxidative mechanism of 4-CP degradation were proved by electron spin resonance (ESR), benzoic capturing, oxygen stripping and 4-CP degradation products. The results show that 4-CP degradation efficiency in the Fe⁰-Al⁰/O₂ system enhanced by EDDS decreases with the initial pH increasing and remains pleasurable in the pH range of 2.5~9. With the mass ratio of Fe⁰ and Al⁰ increasing, the removal rate of 4-CP increases first and then decreases, and the best mass ratio of Fe⁰ to Al⁰ was 4:1. The removal rate of 4-CP increases with EDDS dosage and the initial 4-CP concentration. EDDS was found to have improved 4-CP removal rate by 9times. The complete 4-CP removal and dechlorination were achieved within 3h at nitial pH of 2.5, EDDS dosage of 1.5mmol/L, Fe⁰:Al⁰ (w:w) of 4:1and initial 4-CP concentration of 4-CP of 100mg/L.