MnFe_(2)O_(4)@HTC活化过硫酸盐体系除藻效能与机制  

Performance and mechanism of MnFe_(2)O_(4)@HTC activated persulfate system for algae removal

作　　者：李梦颖 向平[1] 姜文超[1] 张智[1] 莫静宇 LI Mengying;XIANG Ping;JIANG Wenchao;ZHANG Zhi;MO Jingyu(Key Laboratory of the Three Gorges Reservoir Region′s Eco-Environment,Ministry of Education,Chongqing University,Chongqing 400045)

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《环境科学学报》2021年第9期3535-3544,共10页Acta Scientiae Circumstantiae

基　　金：重庆市建设科技项目(城科字2020第5-2)。

摘　　要：采用水热法和共沉淀法将MnFe_(2)O_(4)负载在水热炭(HTC)表面制备磁性MnFe_(2)O_(4)@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MnFe_(2)O_(4)/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MnFe_(2)O_(4)@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MnFe_(2)O_(4)@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1.4×10^(9)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,MnFe_(2)O_(4)@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、1O_(2)、·O_(2)、SO_(4)^(-)和·OH多种氧化物质,使藻细胞破裂死亡.A magnetic MnFe_(2)O_(4)@HTC composite catalyst was prepared by loading MnFe_(2)O_(4) 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 MnFe_(2)O_(4)/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 MnFe_(2)O_(4)@HTC activated PS system on algae removal without oxygen were investigated. The reaction mechanism of MnFe_(2)O_(4)@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 1.4×10^(9) 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, MnFe_(2)O_(4)@HTC could adsorb algal cells on its surface, catalyze PS to produce holes, 1O_(2), ·O_(2)^(-), SO_(4)^(-) 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.

关 键 词：铁酸盐 水热炭 铜绿微囊藻 过硫酸盐 

分 类 号：X131[环境科学与工程—环境科学]