蟹壳基生物炭催化臭氧降解阿特拉津的研究

Catalytic Ozonation Degradation of Atrazine by Use of Crab-Shell-based Biochar

在不同热解温度下制备了一系列蟹壳基生物炭(CSB),并应用于催化臭氧降解阿特拉津(ATZ)的研究中。该文采用BET、TG、SEM、XRD和FT-IR表征手段对生物炭的理化性质和形貌进行分析,在500℃下制备的CSB500的比表面积和孔体积达到最大,对应其表面活性官能团含量最高。同时,系统评价了催化剂投加量、初始pH、天然有机物和阴离子对CSB500/O_(3)体系降解ATZ的影响。结果表明,在500℃下制备的CSB500在催化臭氧降解ATZ表现出优异的催化活性,在15 min内对ATZ的降解率达到99%以上,伪一级反应速率k为0.362 min^(-1),并且CSB500在多次循环实验中对ATZ的降解具有良好的稳定性。猝灭剂实验初步揭示了CSB500/O_(3)体系降解ATZ过程中存在·OH、O_(2)^(·-)和^(1)O_(2)等多种活性氧物种。最后,研究对反应机理提出了合理推测。

A laboratory experiment was conducted for developing a novel catalyst applied to the catalytic ozonation process for the degradation of atrazine(ATZ),which involved preparing a series of crab-shell based biochar(CSB)under the condition of several different pyrolysis temperatures,and its physicochemical properties and morphology were detected and analyzed by BET,TG,SEM,XRD and FT-IR for characterizations.The results demonstrated that CSB500 prepared at 500℃owned the largest specific surface areas and pore volume,and correspondingly the highest content of surface active functional groups.Meanwhile,the effects of catalyst dosage,initial pH(of ATZ containing solution),natural organic matter and different anions on ATZ degradation in CSB500/O_(3)system were systematically evaluated,the results indicated that the CSB500 possessed an excellent catalytic ozonation activity for ATZ degradation,and the degradation rate of ATZ reached 99%within 15 min,and the pseudo first-order reaction rate of ATZ degradation was 0.362 min^(-1).Besides,CSB500 had presented good stability in the multiple cycle experiment;and the radical quenching experiment tentatively showed that·OH,O_(2)^(·-)and^(1)O_(2)were confirmed to be involved in the degradation of ATZ in CSB500/O_(3)system.Consequently,the present study put forward a reasonable speculation on the reaction mechanism.