超重力共沉淀法制备铜基催化剂的研究

采用超重力共沉淀法制备铜基催化剂。考察了超重力反应器转速、沉淀pH值和陈化时间等条件对催化剂物性的影响，采用X射线衍射、热重、扫描电子显微镜、N₂等温吸附-脱附和等离子发射光谱等方法对制备的催化剂物相、孔结构、表面形貌和粒子大小进行了表征。结果表明，用超重力共沉淀法制备铜基催化剂应选取较低的pH值，并且不经过陈化以避免前驱体中出现Cu₂(OH)₂CO₃影响Cu的分散性，超重力反应器转速700r/min；超重力共沉淀法制备的前驱体物相中CuO-ZnO主要以固溶体形式存在；焙烧所得铜基催化剂粒度小，Cu分散度高，存在适宜的孔隙结构和较大的比表面积。

Preparation of a copper-based catalyst by a high gravity co-precipitation method

A high gravity co-precipitation method has been used to prepare a copper-based catalyst,and the effects of varying the rotation speed of the packed bed,pH of precipitation,aging time and other conditions on the properties of the catalyst were investigated.The physical and chemical properties of the resulting catalyst,such as precursor phase,pore structure,surface morphology and particle size,were studied by X-ray diffraction(XRD),thermogravimetric analysis(TG),N2 adsorption/desorption isotherms(BET),scanning electron microscopy(SEM) and inductively coupled plasma-atomic emission spectroscopy(ICP).Preparation of copper-based catalysts by the high gravity co-precipitation method avoids the formation of Cu2(OH)2CO3,which has an adverse effect on dispersion of Cu,since it does not require an aging process and can be operated at a low pH.The optimum speed of the rotating packed bed was found to be 700 r/min.The CuOZnO in the precursor phase was mainly in the form of a solid solution.In comparison with conventional methods,the particle size of the calcined catalyst prepared by the high gravity co-precipitation method is smaller,the dispersion of Cu is more uniform,the pore structure is optimized and the specific surface area is larger.