Ni-Ce/N-rGO催化剂的表征及其催化苯酚加氢制备环己酮的性能

以鳞片石墨、尿素为原料，采用水热法制备了氮掺杂还原氧化石墨烯(N-rGO)载体，然后采用浸渍法制备了不同碱性组分改性的Ni/N-rGO催化剂，将其用于苯酚选择性加氢制备环己酮的反应。并通过N₂吸附-脱附、XRD、FT-IR、SEM和EDS等手段对Ni/N-rGO催化剂进行表征。结果表明：与添加Cu、Fe、Na组分相比，添加组分Ce后Ni/N-rGO催化剂的比表面积和孔径均显著增大，可有效促进金属Ni在载体表面均匀分散，提高催化剂的活性；组分Ce的添加减弱了石墨烯表面含氧官能团的酸性质，有利于提高环己酮的选择性；在反应温度150 ℃、反应压力0.4 MPa、反应时间2.0 h、催化剂用量0.2 g的条件下，Ce/Ni摩尔比0.2时制备的Ni-Ce/N-rGO催化剂作用下，苯酚转化率为95.2%，环己酮选择性为72.6%。

Characterization of Ni-Ce/N-rGO Catalyst and Its Catalytic Performance for Hydrogenation of Phenol to Cyclohexanone

Using flake graphite and urea as raw materials, a nitrogen-doped reduced graphene oxide (N-rGO) carrier was prepared by hydrothermal method, and then Ni/N-rGO catalyst modified with different components was prepared by impregnation method. Later, the catalyst was characterized by means of N₂ adsorption-desorption, XRD, FT-IR, SEM and EDS. The results show that compared with the addition of Cu, Fe, and Na components, the addition of the component Ce can significantly increase the specific surface area and pore diameter of Ni/N-rGO catalyst, thus effectively promoting the uniform dispersion of the metal Ni on the surface of the carrier and improving the activity of catalyst; the addition of the component Ce can weaken the acid properties of the oxygen-containing functional groups on the graphene surface, which is beneficial to improve the selectivity of cyclohexanone; When the following conditions are met: the reaction temperature of 150 ℃, reaction pressure of 0.4 MPa, reaction time of 2.0 h and catalyst amount of 0.2 g, as well as Ni-Ce/N-rGO catalyst prepared at the molar ratio of Ce/Ni of 0.2, the conversion of phenol is 95.2%, and the selectivity of cyclohexanone is 72.6%.