均匀沉淀法制备负载型双金属催化剂的正交实验研究

以NiCl2·6H2O和Co(NO3)2·6H2O为原料,CO(NH2)2为沉淀剂,Al2O3为载体,采用均匀沉淀法制备了负载型双金属催化剂(Ni-Co/γ-Al2O3).利用正交实验探讨了不同工艺参数对催化剂合成的影响,并得出了最佳制备工艺.实验得出的最佳工艺参数为:n(NiCl2·6H2O)/n(Co(NO3)2·...

Orthogonal experiment of a supported bimetallic catalyst prepared by homogeneous precipitation method

The supported bimetallic catalysts（nano-Ni-Co/γ-Al2O3） were prepared by a homogeneous precipitation method involving an aqueous solution of nickel chloride hexahydrate,cobalt nitrate hexahydrate and urea,with alumina as the catalyst carrier.The effects of various technical parameters on the synthesis yield of catalysts were investigated and the optimum processing conditions were found through orthogonal experiments.The optimum processing conditions to prepare Ni-Co/γ-Al2O3 bimetallic catalysts were as follows： the molar ratio of nickel chloride hexahydrate to cobalt nitrate hexahydrate was 4∶1,the molar ratio of urea to metal salts was 6∶1,the reaction temperature was 115℃,the reaction time was 2.5h.Different approaches such as XRD and SEM were adopted to characterize the crystalline structure and morphology of the supported catalysts.The analytical results indicated that the supported catalysts had the composite nanoparticle of nickel and cobalt oxide on the surface of γ-Al2O3 carrier,which is a multi-layered structure with well dispersed.