Applied Catalysis A: General ( IF 5.5 ) Pub Date : 2018-05-31 , DOI: 10.1016/j.apcata.2018.05.039 Xiaolan Zhang , Ye Junhui , Yuan Jing , Cai Ting , Xiao Bei , Liu Zhe , Zhao Kunfeng , Yang Ling , He Dannong
A series of CoaMnbOx oxides (a/b = 1:1∼7:1) at 500 °C and Co2Mn1Ox at a temperature range of 300–700 °C were prepared by an oxalate co-precipitation method and evaluated of catalytic performance for benzene total oxidation. It is found that Co2Mn1Ox catalyst displays the best activity among all the CoaMnbOx oxides. The typical uniform nanosheet morphology plays a vital role in achieving the relatively high activity of Co2Mn1Ox. A detailed characterization has illustrated that the calcination temperature is also an important factor to influence the structure, physico-chemical properties and thus catalytic performance of Co2Mn1Ox. Co2Mn1Ox calcinated at 300 °C (CM300) presents pretty thin nanosheet and small particle size of 6.6 nm. It displays a better low-temperature catalytic activity than those obtained at temperatures of >300 °C: under the conditions of 20,000 mL g−1 h−1 and 1500 ppm of benzene, the temperature at 90% conversion of benzene oxidation is 191 °C, which is lower than that of some related reports in the literatures. Furthermore, CM300 performed excellent long-term stability. It is concluded that the superior catalytic performance of CM300 is associated with its relatively large specific surface area, good low-temperature redox property, abundant active oxygen species and active components (Co2+ and Mn4+). Co-Mn oxides will be the potential alternative of precious metals for the removal of volatile organic compounds in the industrial field.
中文翻译:
纳米片状Co-Mn氧化物对全苯氧化的优异低温催化性能
草酸钴制备了一系列在500°C的Co a Mn b O x氧化物(a / b = 1:1〜7:1)和在300-700°C的温度范围内的Co 2 Mn 1 O x。沉淀法并评估了苯的总氧化催化性能。发现在所有的Co a Mn b O x氧化物中,Co 2 Mn 1 O x催化剂表现出最好的活性。典型的均匀纳米片形态在实现相对较高的Co 2 Mn 1 O x活性方面起着至关重要的作用。。详细的表征表明,煅烧温度也是影响Co 2 Mn 1 O x的结构,理化性质以及催化性能的重要因素。在300°C(CM300)下煅烧的Co 2 Mn 1 O x呈现出非常薄的纳米片和6.6 nm的小粒径。与在> 300°C的温度下(在20,000 mL g -1 h -1的条件下)获得的低温催化活性相比,它显示出更好的低温催化活性。在1500 ppm苯的情况下,苯氧化90%转化时的温度为191°C,低于一些相关报道的温度。此外,CM300具有出色的长期稳定性。结论是,CM300优异的催化性能与其相对较大的比表面积,良好的低温氧化还原性能,丰富的活性氧种类和活性成分(Co 2+和Mn 4+)有关。Co-Mn氧化物将是在工业领域去除挥发性有机化合物的潜在贵金属替代品。