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共轭羰基化合物的羰基选择性加氢反应被广泛用于制备重要的药物和化学中间体.利用氮掺杂碳纳米笼(hNCNC)大的比表面积和掺杂氮原子的锚定作用,构建了10 wt%Ru负载量的Ru/hNCNC催化剂,尺寸约2.4 nm的Ru纳米颗粒高度均匀地分散在hNCNC表面.用于催化苯乙酮选择性加氢制1-苯乙醇,在50.0℃、2.0 MPa H_2的温和条件下,展现出优异的催化加氢性能:反应2.0 h后的苯乙酮转化率和1-苯乙醇选择性分别达到96.2%和95.8%,远优于未掺杂碳纳米笼(h CNC)和活性炭负载的Ru催化剂;循环使用6次后,其苯乙酮转化率仅略有下降(从96.2%到94.0%),明显优于Ru/h CNC.Ru/hNCNC的优异催化性能可归因于:hNCNC大的比表面积和掺杂氮原子的锚定作用有利于Ru纳米粒子的分散和固载、独特的微孔-介孔-大孔共存的分级孔结构有利于传质、掺杂氮原子有效调变了Ru催化剂的电子结构.
Carbonyl selective hydrogenation of conjugated carbonyl compounds has been widely used in the preparation of important pharmaceutical and chemical intermediates.Using the large specific surface area of nitrogen-doped carbon nanocages (hNCNC) and the anchoring effect of nitrogen-doped atoms, Ru / hNCNC catalyst with a loading of 10 wt% Ru and Ru nanoparticle with a size of about 2.4 nm were highly uniformly dispersed on the surface of hNCNC.This catalyst was used to catalyze the selective hydrogenation of acetophenone to 1-phenylethanol at 50.0 ℃ and 2.0 MPa H 2 under mild conditions, showing excellent performance of catalytic hydrogenation: after 2.0 h of conversion of acetophenone and 1-phenyl-ethanol selectivity of 96.2% and 95.8%, far superior to the undoped carbon nanocage h CNC) and activated carbon supported Ru catalyst. After six cycles, the conversion of acetophenone decreased only slightly (from 96.2% to 94.0%), which was significantly better than the excellent catalytic performance of Ru / h CNC.Ru/hNCNC It is attributed to the fact that the large specific surface area of hNCNC and the anchoring effect of doped nitrogen atoms are conducive to the dispersion and immobilization of Ru nanoparticles. The unique hierarchical pore structure coexisting with micropores, mesopores and macropores is good for mass transfer, Doping nitrogen atoms effectively modulate the electronic structure of Ru catalyst.