Pluronic F127辅助水热法制备CexZr1−xOy室温催化氧化甲醛

Pluronic F127-assisted hydrothermal synthesis of CexZr1−xOy for room temperature catalytic oxidation of formaldehyde

  • 摘要: 以水热法制备催化剂CexZr1xOy用于室温下催化氧化甲醛,各添加模板剂聚乙二醇、Pluronicf127后,发现添加Pluronicf127的FCexZr1xOy催化剂对甲醛催化氧化活性高于另外两者. 在此基础上深入探究了F127作为模板剂时,Ce/Zr添加量各为5 mmol的不同F127添加量、固定F127添加量下,Ce/Zr不同摩尔比、焙烧温度等条件下所制备的具有介孔材料的FCexZr1xOy室温下催化氧化甲醛性能的影响,并采用BET、SEM、IR、XPS、XRD、N2吸附脱附对催化剂进行表征,结果表明:Ce/Zr掺杂量各为5 mmol、F127添加量为1.5 g、焙烧温度为500 ℃时,催化氧化甲醛活性最佳. 其中Ce/Zr掺杂比例使催化剂的晶粒尺寸、Ce3+含量、比表面积等存在明显差异,FCe0.5Zr0.5催化剂的Ce3+含量最高,具有最大比表面积111 m2/g和孔容0.124 cm3·g−1,6 h内表现出甲醛最佳转化率,为84.69%. 反应后催化剂氧空位吸附氧和比表面积大幅降低,晶格氧含量升高,催化剂失活.

     

    Abstract: In this paper, the catalyst CexZr1-xOy was prepared by the hydrothermal method for catalytic oxidation of formaldehyde at room temperature, and it was found that the FCexZr1-xOy catalyst with Pluronicf127 was higher than the other two when the template agents polyethylene glycol and Pluronicf127 were added. Effect of FCexZr1−xOy prepared with mesoporous materials on the properties of formaldehyde oxidation at room temperature under different molar ratios and firing temperatures, using BET, SEM, IR, XPS, XRD, and N2 adsorption-desorption techniques. The results showed that the catalytic oxidation of formaldehyde was the best when the Ce/Zr doping amount was 5 mmol, the F127 addition was 1.5 g, and the roasting temperature was 500 ℃. The Ce/Zr doping ratio made the grain size, Ce3+ content and specific surface area of the catalyst significantly different, and the FCe0.5Zr0.5 catalyst had the highest Ce3+ content, with a maximum specific surface area of 111 m2/g and a pore volume of 0.124 cm3·g−1, and showed the best formaldehyde conversion rate of 84.69% within six hours. After the reaction, the oxygen vacancy of the catalyst adsorbed oxygen and the specific surface area was greatly reduced, the lattice oxygen content increased, and the catalyst was inactivated.

     

/

返回文章
返回