Preparation And Isomerization Performance Of SAPO-11 Molecular Sieves

With the increasing awareness and increasingly strigent regulations of environment protection, currently the demands for clean gasoline and diesel as well as high-quality lubricants are kept expanding. Consequently, the hydroisomerization of the normal paraffinic hydrocarbons, an approach of producing top-quality petroleum products has drawn more and more attention. Among them, the hydroisomerization of heptane is of great importance in increasing the front-end octane number of gasoline and improving the viscosity temperature relationship of diesel.We synthesized SAPO-11 mesoporous sieves using water-heat synthesis, prepared Ni or NiW loaded on SAPO-11 catalysts, investigated isomerization of n-heptane on these catalysts, discussed the effect of different preparation conditions, reduction conditions and reaction conditions on the conversion and isomerization selectivity of n-heptane. The main contents of the thesis were discussed as follows:The isomerization of n-heptane on Ni/SAPO-11 catalysts was investigated. The result showed that the conversion of n-heptane and isomerization selectivity to i-heptane can reach 61.67% and 70.67% on Ni/SAPO-11 catalyst when content of Ni is 2%, H2 reduction temperature is 430℃, reducted for 4h, flow rate of H2 is 30mL/min, and reaction temperature is 320℃.The isomerization of n-heptane on NiW/SAPO-11 catalysts was investigated. The result showed that the conversion of n-heptane and isomerization selectivity to i-heptane can reach 40.77% and 68.15% on NiW/SAPO-11 catalyst when content of Ni is 2%, the content of W is 15%, H2 reduction temperature is 420℃, reducted for 4h, flow rate of H2 is 30mL/min, and reaction temperature is 290℃.