摘要2,4-DNT作为一种常见的污染物,由于其结构稳定,物质复杂且难以降解,一直以来都是化学处理上的难题。由Eisenhouser HR开创的Fenton法因其反应条件简单,降解效率高成为主流的方法。但是寻求高效简便的催化剂就成了研究的重点。63822
本文提出了一种新型催化剂。这种催化剂是以传统FeOOH为主体,混合添加了金属氧化物MnOOH并将其负载在有序介孔材料SBA-15以增强其稳定性。通过X射线衍射,扫描电镜对催化剂进行结构表征。论文考察了新型催化剂对水中二硝基苯类化合物的降解能力,探求了最佳条件下降解硝基苯的效率和不同反应条件下对硝基苯降解效率的影响,并研究催化剂对硝基苯的降解机理。结果表明:
(1) 在pH=5,H2O2浓度为4.9897mmol/L,催化剂浓度为1g/L,温度为50℃反应1h时达到最佳降解条件,降解效率为96%。
(2) 在不同反应条件下催化剂浓度对降解效率的影响最大,其次就是H2O2浓度的影响, 两者是协同作用的。催化剂降解硝基苯的机理是催化剂促使H2O2释放出·OH,·OH与硝基苯作用使硝基苯发生以下变化:硝基苯→亚硝基苯→苯基羟胺→苯胺。
(3) 对催化剂进行重复性试验可以知道本催化剂具有较好的催化效果和很好的稳定性。
毕业论文关键词: FeOOH/MnOOH,SBA-15,2,4-DNT,吸附降解,协同作用,反应机理
毕业设计说明书(论文)外文摘要
Title Mesoporous Silica-supported FeOOH-MnOOH phase Fenton degradation of DNT study
Abstract Nitrobenzene as a common contaminant,has been the problem of the chemical treatment due to its structural stability, the complex material and difficult to degrade. Pioneered by the Eisenhouser HR Fenton method become a mainstream method because of its simple reaction conditions , the degradation efficiency. But seeking an efficient and simple catalyst has become the focus of the study .
This paper presents a novel catalyst. This catalyst is based on traditional FeOOH as the main body , mixed metal oxides MnOOH added and the load in the ordered mesoporous SBA-15 materials to enhance its stability.
the novel catalyst was characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM). It examines the new catalyst for the degradation of trace nitrobenzene , and explore the optimal condition, the degradation efficiency of nitrobenzene under different reaction conditions and the degradation efficiency of nitrobenzene , and study the degradation of nitrobenzene catalyst mechanism.
(1) At PH = 5, H2O2 concentration of 4.9897mmol / L, the catalyst concentration was 1g / L, the reaction temperature is 50 ℃ 1h achieve the best degradation conditions , and the resulting degradation efficiency was 96%.
(2) At different concentrations of catalysts under reaction conditions the greatest impact on the degradation efficiency , followed by concentration of H2O2 , the two are synergistic. The mechanism of photocatalytic degradation of nitrobenzene H2O2 catalyst to promote the release of • OH, The Pathway of nitrobenzene reduetion by • OH was deseribed as: nitrobenzene→nitrosobenzene→phenylllyoxylamine→aniline.
(3) through repetitive test can be the catalyst that has a good reuse can be further deepened in order to be used in industrial production.
Keywords: FeOOH/MnOOH,SBA-15, nitrobenzene, adsorption and degradation,Synergetic effect, mechanism
1 引言1
1.1 一般研究方法1
1.1.1