Synthesis Of Mesoporous Transition Metal Oxide Catalysts For Catalytic Oxidation Of Benzyl Alcohol

The catalytic oxidation of benzyl alcohol is vitally important in modern chemical industry because the obtained benzaldehyde product is an indispensable intermediate for fine chemicals and pharmaceutical synthesis.Traditionally,industrial method to produce benzaldehyde was usually used in the hydrolysis of benzyl chlorinated,leading to complex process,difficulties in product separation,and chlorine and other harmful substances mixed in the product,severely limiting its applications.During the past decade,the market demand for benzaldehyde has been increasing,and the reaction of benzaldehyde for the oxidation of benzyl alcohol with pure oxygen or air as oxidant has become environmentally friendly and has become one of the main ways to obtain "green" products.These procedures have inherent drawbacks,such as difficulty in catalyst separation and regenerability,utilization of unsafe and expensive oxidants resulting in serious environmental pollution and loss of industrial interests.In the rapid development of catalyst preparation and separation technology today,to heterogenize homogeneous catalysts by anchoring them onto insoluble supports is a possible strategy to overcome this difficult.Therefore,the development of heterogeneous catalytic systems operating with environmentally friendly oxidants has caused great interest.The main method is as follows:1?Highly efficient Ni-Co oxide nanoparticles on nitrogen-doped FDU-15 for aerobic benzyl alcohol oxidationNi-Co bimetallic oxide catalysts with various loadings and Ni/Co ratios supported on N-doped FDU-15 were prepared by a facile and controllable one-pot method and tested as heterogeneous catalysts for the oxidation of benzyl alcohol.When air was used as an oxidizing agent at 110 °C,Catalytic results showed that 2 wt.% Ni-Co₃/FDU-15-N had a high substrate conversion?93.4%?and exceptional benzaldehyde selectivity?97.8%?.This superior catalytic performance over bimetallic catalysts indicated a synergy effect between Ni and Co.The improved redox ability and dispersion of Ni-Co alloying sites also contributed to this enhancement. Additionally,N-doped Ni-Co₃/FDU-15-N might strengthen the interaction between Ni O,Co₃O₄ and the support and thus improve the dispersion of the metal oxides.2?Synthesis of three-dimensional ordered mesoporous cobalt oxides for selective oxidation of benzyl alcoholSelective oxidation of benzyl alcohol to benzaldehyde has been investigated extensively since benzaldehyde is a wildly used industrial raw material to produce lauric,lauryl aldehyde acid,phenylacetaldehyde,benzyl benzoate,etc.Herein,we synthesized an ordered 3D mesoporous Co₃O₄?denoted as 3D-Co₃O₄?from cubically ordered mesoporous silica?KIT-6?hard template.The structural and textural properties were well characterized by XRD,SEM,TEM,N2 adsorption and desorption and XPS.Catalytic results showed that 3D-Co₃O₄ displayed far better catalytic performance?86.7% conversion?than commercial Co₃O₄?49.5% conversion?in the oxidation of benzyl alcohol when air was used as oxidant.