Ni含量对NiO/CeO_(2)催化剂催化CO氧化性能的影响

Effect of Ni content on catalytic oxidation of CO over NiO/CeO_(2) catalyst

以CeO_(2)为载体,Ni为活性组分,采用球磨法制备了低温条件下性能较好的CO氧化NiO/CeO_(2)催化剂。通过XRD、BET、H_(2)-TPR、XRF和XPS等技术对催化剂进行了表征,考察了镍含量对催化剂结构和CO低温氧化性能的影响。结果表明,不同Ni/Ce比主要影响催化剂表面晶格氧空位的数量以及活性组分和载体之间的相互作用。其中,Ni/Ce物质的量比为1∶9时,催化剂表面氧空位数量较多,因此,表现出优良的催化性能。在反应温度为200℃、氧过量系数为5、气体总空速为60000 mL/(g_(cat)·h)的条件下,CO转化率为99.2%。此外,与传统液相制备催化剂技术相比,球磨法具有污染小、成本低、易操作等特点,有利于节约能源。

The NiO/CeO_(2) catalytic materials were prepared with ball milling method using CeO_(2) as carrier and Ni as active component with good CO oxidation performance at low temperature.The catalysts were characterized by XRD,BET,H_(2)-TPR,XRF and XPS.The effects of nickel content on the structure and low temperature oxidation performance of CO were investigated.The results show that the Ni-Ce ratio mainly affects the number of lattice oxygen vacancies and the interaction between the active ingredient and the carrier.Among them,When the Ni/Ce mole ratios is 1∶9,there are more oxygen vacancies on the surface of the catalyst,so it shows excellent catalytic performance.When the reaction temperature is 200℃,oxygen excess coefficient is 5 and the total space velocity is 60000 mL/(g_(cat)·h),the CO conversion reaches 99.2%.In addition,compared with the traditional liquid phase catalyst preparation technology,ball milling has the advantages of low pollution,low cost and easy operation,which is beneficial to save energy.