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碳-氧键氢解是生物质呋喃基化合物制备交通燃料常见的模型反应,其中5-羟甲基糠醛(HMF)转化为汽油添加剂2,5-二甲基呋喃(DMF)尤为引人关注.本文采用CeO_2,ZrO_2和Al_2O_3负载的Cu-Co双金属催化剂用于HMF选择性氢解制DMF的反应中.采用X射线衍射、N_2吸附-脱附、投射电镜、H_2-程序升温还原、氨-程序升温脱附和元素分析表征了新鲜的和使用过催化剂的结构,并将其与催化活性相关联.Cu-Co/CeO_2催化剂通过在大的Cu颗粒上还原C=O键生成了最多的2,5双(羟甲基呋喃)(BHMF).但Cu-Co/Al_2O_3催化剂具有高度分散的Cu,Cu-Co复合氧化物和大量的弱酸位,因而生成DMF的选择性最高.Cu-Co/ZrO_2催化剂则由于存在强酸位,DMF选择性较低,生成了各种过度氢解产物,如2,5而甲基四氢呋喃和5,5-二(亚甲基)双(2-甲基呋喃).因此,考察了Cu-Co/Al_2O_3催化剂上的反应路径,以及温度、氢气压力和时间等操作条件的影响,使其具有较优的HMF转化率和DMF选择性.
Carbon-oxygen bond hydrogenolysis is a common model reaction for the production of transportation fuels from biomass furanyl compounds, of which 5-hydroxymethylfurfural (HMF) is converted into gasoline additive 2,5-dimethylfuran (DMF) is of particular concern. In this paper, Cu-Co bimetallic catalysts supported on CeO_2, ZrO_2 and Al_2O_3 were used for the selective hydrogenolysis of DMF to DMF.Using X-ray diffraction, N 2 adsorption-desorption, projection electron microscopy, H 2- Temperature-programmed desorption and elemental analysis characterize the fresh and used catalyst structure and relate it to the catalytic activity.Cu-Co / CeO_2 catalyst produced the most 2 by reducing C = O bonds on large Cu particles, However, the Cu-Co / Al 2 O 3 catalyst has the highest selectivity for DMF due to the highly dispersed Cu, Cu-Co complex oxide and a large amount of weak acid sites. Due to the presence of strong acid sites, the catalyst is less selective and produces a variety of over hydrogenolysis products such as 2,5-methyltetrahydrofuran and 5,5-bis (methylene) bis (2-methylfuran). Therefore, the reaction path on the Cu-Co / Al 2 O 3 catalyst was investigated, as well as the operating conditions of temperature, hydrogen pressure and time Ring, it has superior HMF conversion and selectivity DMF.