铁酸铜非均相活化过硫酸盐降解罗丹明B

采用新型磁性催化材料尖晶石型铁酸铜（CuFe₂O₄）活化过硫酸盐（PMS）降解氧杂蒽类染料罗丹明B（RhB），考察PMS浓度、CuFe₂O₄投加量、pH值和水中常见离子对RhB降解的影响.结果表明，当RhB、PMS、CuFe₂O₄初始浓度分别为5 μmol/L、0.1mmol/L、0.1g/L时，在中性条件下反应30min后RhB去除率可达88.87%.其中，Cl^-和HCO₃^-对RhB的降解无显著影响，而H₂PO₄^2-、C₂O₄^2-及腐殖酸明显抑制RhB的降解.自由基鉴定实验表明，在中性及弱碱性条件下SO₄^-和·OH是CuFe₂O₄/PMS体系降解RhB的主要自由基.研究发现随着RhB的降解，溶液逐渐褪色并伴随着甲酸根、乙酸根、草酸根和铵根离子的生成，原因在于SO₄^-和·OH可以破坏RhB分子的发色基团，使苯环开环和氮原子脱落，形成相应的降解产物.矿化实验表明0.2mmol/L的RhB在CuFe₂O₄/PMS体系中反应10h后，矿化率可达62%.催化剂的重复利用实验表明制备的CuFe₂O₄具有良好回收再利用能力.

Degradation of rhodamine B by heterogeneous activation of persulfate with copper ferrate

In this study, a novel magnetic catalytic CuFe₂O₄, was synthezed and used to activate peroxymonosulfate (PMS) to degrade Rhodamine B (RhB) which is an anthracene dye. The effects of PMS concentration, CuFe₂O₄ dosage, solution pH, inorganic ions and natural organic matter on RhB degradation were investigated. The results showed that the RhB removal reached 88.87% after 30min reaction under neutral pH conditions when the initial concentrations of RhB, PMS and CuFe₂O₄ were 5μmol/L, 0.1mmol/L and 0.1g/L, respectively. And Cl^-, HCO₃^- had no significant effect on the degradation of RhB, while H₂PO₄^2-,C₂O₄^2- and humic acid had significant inhibition on the degradation of RhB. Free radical identification experiments showed that SO₄^- and·OH were the main free radicals in the system of CuFe₂O₄/PMS under neutral and weak alkaline conditions. It was found that the solution gradually fades and the formate, acetate, oxalate and ammonium ions were producedin the process of RhB degradation. This is attributing to the destruction of the chromophore on RhB molecule upon SO₄^- and·OH attacks, leading to the opening of benzene ring and the falling off of nitrogen atom. The mineralization experiment showed that when 0.2mmol/L of RhB was degraded in the CuFe₂O₄/PMS system for 10h, the mineralization rate reached 62%. Catalyst recycling experiments showed that the prepared CuFe₂O₄ had a good recycling ability.