载体对生物质油裂解镍基催化剂的性能影响

Influence of the Carrier on the Performance of Nickel Base Catalyst in the Catalytic Cracking Reaction of Biomass Oil

以改性处理的CaA分子筛、硅藻土和ZrO_2-CeO_2复合氧化物为载体,分别负载镍制备催化剂,并采用XRD、SEM、TPR、TG、FT-IR对催化剂的结构、形貌、表面酸中心种类、还原性能和积碳性能等进行了表征。结果表明,载体的种类影响催化剂性能,改性后的Ca A分子筛具有较大的比表面积和孔容,负载镍基催化剂表面具有较强的L酸和B酸中心,能与镍物种形成较强的相互作用,在生物质油催化裂解反应中表现出较好的活性,同时催化剂表面较强的酸中心也促进了积碳前驱物的形成;而Ni O/硅藻土催化剂和NiO/ZrO_2-CeO_2催化剂的酸中心强度相对较弱,影响了活性组分与载体的相互作用,活性组分在反应中烧结现象明显。

The modified GaA zeolite, diatomite and ZrO2 - CeO2 composite oxide are used as carriers, and supported nickel catalysts are prepared by loading nickel separately. Then the XRD, SEM, TPR, TG and FT - IR, are used to characterize the catalytic struc-tures, morphologies, surface acid sites, reduction properties and carbon deposition of the catalysts. The result shows that, vectors are different, because the structure of the carrier influences the catalytic performance. The modified GaA zeolite has a larger specific surface area and pore volume, and the surface of supported nickel based catalysts has a stronger center of L and B acid, which can make the stronger interaction with nickel species. It shows good activity in catalytic cracking reaction of biomass oil, and the stron-ger acid sites on the catalyst surface also promote the formation of carbon precursor, with evident carbon deposition. The acid center strength of the NiO/diatomite and NiO/ZrO2 - CeO2 catalysts are relatively weak, which affect the interaction between the active component and carrier. The active components are sintered obviously in the reaction.