Abstract:

Cobalt ferrate （CoFe₂O₄） particles were added into solution containing peroxodisulfate （PDS） to construct a PDS/CoFe₂O₄ catalytic oxidation system， for treating tetracycline （TCH） organic wastewater. X-ray diffraction （XRD） and Fourier infrared spectroscopy （FT-IR） results showed the successful preparation of CoFe₂O₄ particles. In the PDS/CoFe₂O₄/TCH system， the effects of PDS dosage， CoFe₂O₄ dosage， initial concentration of TCH and initial pH on the catalytic oxidation of TCH by CoFe₂O₄-activated persulfate and the reusability of the CoFe₂O₄ particles were focused on. The experimental results showed that the removal rate of TCH was positively correlated with the dosage of PDS and CoFe₂O₄， and negatively correlated with the initial concentration of TCH. Acidic conditions favored the removal of TCH， and the removal rate of TCH slightly decreased under neutral and alkaline conditions. The CoFe₂O₄ particles showed good removal effect on TCH after 10 times of reuse in the PDS/CoFe₂O₄ system， indicating that the CoFe₂O₄ have high stability and continuous catalytic activity. CoFe₂O₄ activated persulfate oxidation of TCH was mainly a heterogeneous reaction. In addition， the CoFe₂O₄ catalyst was applied to continuous flow tubular reactor， and the catalyst could be immobilized rapidly by using CoFe₂O₄ particles’ magnetism. The removal rate of 25 mg/L TCH wastewater was above 90% at a hydraulic retention time of 31 min.

Key words: CoFe₂O₄, persulfate, tetracycline, antibiotic, advanced oxidation

摘要：

将自制铁酸钴（CoFe₂O₄）颗粒投入含过二硫酸盐（PDS）的溶液中，构建PDS/CoFe₂O₄催化氧化体系，处理四环素（TCH）有机废水。X射线衍射（XRD）和傅里叶红外光谱（FT-IR）表征结果显示成功制备出CoFe₂O₄颗粒。在PDS/CoFe₂O₄/TCH体系中，重点考察了PDS投加量、CoFe₂O₄投加量、TCH初始浓度和初始pH等因素对CoFe₂O₄活化过硫酸盐催化氧化水中四环素的影响，以及自制CoFe₂O₄颗粒的重复利用性。实验结果表明：四环素的去除率与PDS和CoFe₂O₄的投加量呈正相关，与TCH初始浓度呈负相关；酸性条件有利于TCH的去除，中性和碱性条件下TCH的去除率略有下降；自制CoFe₂O₄颗粒在活化过硫酸盐体系中重复利用10次后，对TCH仍表现出很好的去除效果，说明自制CoFe₂O₄颗粒具有较高且持续稳定的催化活性。CoFe₂O₄颗粒活化PDS催化氧化去除TCH有机废水的体系以非均相催化反应为主。此外，将CoFe₂O₄催化剂应用于自制的连续流管式反应器中，利用CoFe₂O₄颗粒自身磁性可实现催化剂的快速固定化。水力停留时间为31 min时，25 mg/L四环素废水的去除率稳定在90%以上。

关键词: CoFe₂O₄, 过硫酸盐, 四环素, 抗生素, 高级氧化

CLC Number: 

• X703