Cu_xO_y空心球催化苯甲醛制苯甲酸

Preparation of benzoic acid from benzaldehyde catalyzed by Cu_xO_y hollow spheres

以CuSO_4和蔗糖为前驱体,水热合成含碳的铜氧化物后,采用空气焙烧除去碳,合成了空心球型的Cu_xO_y样品.Cu_xO_y样品为CuO和Cu_2O纳米粒子紧密聚合而形成的空心球结构,粒径大小在0.5～0.8μm之间.制备的Cu_xO_y-550℃-4h样品(550℃空气热处理4h)存在Cu_2O和CuO两种氧化物,当550℃空气热处理10h和750℃空气热处理4h时,样品以CuO的形式存在.Cu_xO_y-550℃-10h催化剂的活性最高.以乙腈为溶剂,苯甲醛0.5mL,过氧化氢2mL,催化剂0.1g,60℃反应3h,苯甲醛的转化率和苯甲酸的选择性分别达到了80%和99.4%.同时显示出较好的稳定性.

The hollow sphere CuxOy samples were prepared by hydrothermal and calcination in air atmosphere CuSO4and sucrose as precursors.The catalysts were characterized by XRD,TG,FT-IR,SEM.The results indicated that CuxOy sample are hollow spheres with a diameter of0.5~0.8μm,which were formed by tightly aggregation of CuO/Cu2O or CuO nanoparticles.When the Cu x O y sample was calcinated in air at550℃for4h,it composed of CuO/Cu2O nanoparticles.When the CuxOy sample was calcinated at550℃for10h or at750℃for4h,they composed of CuO nanoparticles.Under optimized reaction conditions,the benzoic acid yield and selectivity reached80%and>99.4%over CuxOy-550℃-10h,respectively.Meanwhile,the catalyst shows a better reusability.