LaFeO_(3)钙钛矿催化剂的制备及其对苯酚的降解处理

Preparation of LaFeO_(3) perovskite catalyst for the degradation of phenol

采用球磨、溶胶凝胶和共沉淀3种方法制备了LaFeO_(3)钙钛矿催化剂前驱体,通过改变焙烧温度获得了一系列LaFeO_(3)钙钛矿催化剂。利用XRD、FT-IR、N2物理吸脱附、H2-TPR和XPS等手段对催化剂的结构和性质进行了表征,并考察了其催化湿式空气氧化苯酚性能。结果表明,制备方法对催化性能有较大影响。同时低温还原能力强、氧空位多的催化剂催化活性较高。采用溶胶凝胶法,800℃焙烧制备的催化剂的催化活性较好,在反应温度为200℃,空气压力为5 MPa,苯酚初始浓度为4000 mg·L^(-1)的条件下,最终(240 min)的COD去除率为95.4%。

LaFeO_(3)perovskite catalyst precursors were prepared by ball milling,sol-gel and co-precipitation.A series of LaFeO_(3)perovskite catalysts were obtained by changing the calcination temperature.The structure and properties of the catalyst were characterized by XRD,FT-IR,N2 physical adsorption/desorption,H2-TPR and XPS,and the catalytic performance of the catalyst for wet air oxidation of phenol was investigated.Preparation method of precursors has great influence on the catalytic performance.At the same time,the low temperature reduction ability and more oxygen vacancies of the catalyst have higher catalytic activity.The catalyst prepared by sol-gel method and calcinated at 800℃has good catalytic activity.Under the conditions of reaction temperature at 200℃,air pressure at 5 MPa and initial phenol concentration at 4000 mg·L^(-1),the final COD removal rate(240 min)is 95.4%.