李梦颖,向平,姜文超,张智,莫静宇.MnFe2O4@HTC活化过硫酸盐体系除藻效能与机制[J].环境科学学报,2021,41(9):3535-3544
MnFe2O4@HTC活化过硫酸盐体系除藻效能与机制
- Performance and mechanism of MnFe2O4@HTC activated persulfate system for algae removal
- 基金项目：重庆市建设科技项目（城科字2020第5-2）
- 李梦颖
- 重庆大学三峡库区生态环境教育部重点实验室, 重庆 400045
- 向平
- 重庆大学三峡库区生态环境教育部重点实验室, 重庆 400045
- 姜文超
- 重庆大学三峡库区生态环境教育部重点实验室, 重庆 400045
- 张智
- 重庆大学三峡库区生态环境教育部重点实验室, 重庆 400045
- 莫静宇
- 重庆大学三峡库区生态环境教育部重点实验室, 重庆 400045
- 摘要：采用水热法和共沉淀法将MnFe2O4负载在水热炭（HTC）表面制备磁性MnFe2O4@HTC复合催化剂.采用SEM、XRD、BET、FTIR、XPS对催化剂进行表征，通过考察MnFe2O4/HTC负载比、过硫酸钠（PS）投加量、初始pH和不同化学体系对除藻效果的影响，探究无供氧条件下MnFe2O4@HTC活化PS体系除藻的效能.基于自由基屏蔽实验和XPS分析对MnFe2O4@HTC活化PS体系反应机制进行研究验证.结果表明，当初始藻浓度为1.4×109个·L-1（OD680=0.14），催化剂投加量为0.2 g·L-1，PS投加量为0.4 g·L-1，pH为6时，降解30 min，该体系除藻率可达到99%.在该体系中，MnFe2O4@HTC材料可将藻细胞吸附在材料表面，通过Mn、Fe的价态循环和HTC的协同效应反应催化PS产生空穴、1O2、·O2-、SO4-·和·OH多种氧化物质，使藻细胞破裂死亡.
- Abstract：A magnetic MnFe2O4@HTC composite catalyst was prepared by loading MnFe2O4 on the surface of the hydrothermal carbon (HTC) with hydrothermal-coprecipitation method. Through the Characterization by SEM, XRD, BET, FTIR and XPS, the effects of MnFe2O4/HTC load ratio, sodium persulfate (PS) dosage, initial pH and different chemical systems on algae removal performance of the catalyst were investigated, and the effects of MnFe2O4@HTC activated PS system on algae removal without oxygen were investigated. The reaction mechanism of MnFe2O4@HTC activated PS system was verified based on free radical quencing experiments and XPS analysis. The results indicated that when the initial algae concentration was 1.4×109 cell·L-1 (OD680=0.14), the catalyst dosage was 0.2 g·L-1, the PS dosage was 0.4 g·L-1, and the pH was 6, the algae removal rate reached 99% after 30 minutes of reaction. In this system, MnFe2O4@HTC could adsorb algal cells on its surface, catalyze PS to produce holes, 1O2, ·O2-, SO4-· and ·OH by the valence cycle of Mn and Fe as well as the synergistic reaction of HTC, and then made algal cells to burst and die.
