摘要
以钛基锡锑电极为阳极,研究了电化学氧化技术对水中四环素的去除效果。考察了电流密度(5~25 mA·cm^(-2))、极板间距(5~25 mm)、四环素初始浓度(5~100 mg·L^(-1))和电解质种类(NaClO_4、Na_2SO_4和NaNO_3)对四环素电化学降解效率的影响。研究表明:钛基锡锑电极电化学降解四环素反应符合一级反应动力学规律(R^2>0.95);四环素降解效率随电流密度增大而增大,当电流密度大于15 mA·cm^(-2)时,四环素的降解反应受传质控制;四环素降解效率随极板间距增大而减小,在传质控制条件下,反应速率与极板间距成反比;初始浓度小于20 mg·L^(-1)时,受传质影响,四环素降解效率基本不随初始浓度变化,当初始浓度大于20 mg·L^(-1)时,四环素降解效率随初始浓度增大而减小;Na_2SO_4为电化学降解水中四环素较合适的电解质。
A Ti/SnO2-Sb anode was prepared and used for the electrochemical oxidation of tetracycline （TC）. The effects of reaction conditions including current density （5 to 25 mA · cm-2） , distance between anode and cathode （5 to 25 mm）, initial TC concentration （5 to 100 mg· L-1） and electrolyte （NaClO4, NaESO4 and NaNO3） on the electrochemical degradation kinetics of TC were investigated. The electrochemical oxidation of TC by Ti/SnO2-Sb anode followed pseudo-first-order kinetics （R2 〉 0.95）. The TC degradation efficiency increased with the applied current density. When the applied current density was higher than 15 mA·cm-2, the removal of TC was under the control of mass transfer and its removal efficiency was inversely proportional to the distance between anode and cathode. The degradation efficiencies of TC were almost the same when the initial TC concentration was less than 20 mg· L-1 and showed a decrease trend when it was higher than 20 mg· L-1, indicating that the anode oxidation under low substrate concentration or high current density was controlled by mass transfer. Na2SO4 was suitable supporting electrolyte for TC electrochemical degradation.
出处
《环境工程学报》
CAS
CSCD
北大核心
2018年第1期57-64,共8页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(20907072)
关键词
四环素
电化学氧化
钛基锡锑电极
反应动力学
tetracycline
electrochemical oxidation
Ti/SnO2-Sb anode
reaction kinetics
