S_2O_8~(2-)/CaO·Fe_2O_3光催化降解罗丹明B的研究

采用共沉淀法合成新型催化剂S2O28-/CaO.Fe2O3粉体。用红外光谱对其结构进行表征,并考察了助催化剂H2O2的用量、催化剂的投加量以及不同光源对罗丹明B溶液催化降解的影响。实验结果表明,所研制的S2O28-/CaO.Fe2O3粉体为固体超强酸,粒径处于纳米数量级,且其在紫外光区556 nm处有个紫外特征峰。在浸渍液(NH4)2S2O8浓度为0.5 mol/L、S2O28-/CaO.Fe2O3投加量为0.03g/25 mL、H2O2用量为1.00 mL/25 mL下,对浓度为0.6 g/L的罗丹明B溶液在自然光下静置1 h,其降解率可达99.2%。同时还初步探讨了催化降解过程中物理现象与化学性质分析、酸中心的形成机理及催化剂失活的可能原因。

Study on photocatalisitic degradation of Rhodamine B by S2O82-/CaO.Fe2O3

A new type of S2O2-8/CaO·Fe2O3 powder is produced through Chemical coprecipitation method.Its structure is characterized with the help of IR structure.The writer also analyzes the impact of H2O2 and catalyst dosages and different light sources upon the degradation of rhodamine B.It can be concluded from the experiment that the subject of the S2O2-8/CaO·Fe2O3 powder is solid super acid,diameter is in a nano-size order of magnitude and there is a characteristic peak UV at the point of the District 556 nm in the UV.Meanwhile,with soaking liquid(NH4) 2S2O8 concentration being 0.5 mol / L,S2O2-8/CaO·Fe2O3 dosage 0.03 g/25mL and H2O2 amount 1.00 mL/25mL,the degradation rate could arrive at 99.2 percent if rhodamine B solution with the concentration of 0.6 g / L is placed intact in natural light for about one hour.The writer also discusses the possible causes of the physical phenomenon in the process of catalytic degradation,the formation mechanism of acid center as well as catalyst deactivation.