Light Alkanes Isomerization Behavior Research On SAPO Catalyst

As people increasingly concerned about environmental issues,efficiency,energy saving,environmental protection has been the theme of many areas of petroleum processing indu stry.SAPO-11 has been prepared as a carrier alkane isomerization catalyst,because of its h igh isomerization selectivity characteristics and less environmental pollution.Although the f ocus of the research has been noticed,but there are still several deficiencies,such as zeolit e synthesis methods need tobe improved,choose another metal,etc.,all above need to be st udied.In this paper,SAPO-11 molecular sieve prepared by hydrothermal synthesismethod.Ma inly examines the teamplate agent,crystallization temperature,crystallzation time,PH,water a nd the roasting temperature influence on the synthesis of SAPO-11 molecular sieve.The e xperimental results show that: when the template agent for DIPA+DPA template agent, w ater content is n(Al2O3):n(H2O)=1:30,PH 6.0,crystallization 24 h under 200℃,Roasting 4h u nder 550℃,can get pure SAPO-11 molecular sieves.We take the SAPO-11 molecular sieve as the carrier and preparation the Ni/SAPO-11,Ni Ce/SAPO-11 catalyst.Studied the n-heptane isomerization reaction on the catalyst.Studi ed the preparation conditions,reduction of catalyst and reaction conditions on the perform ance impact of n-heptane isomerization reaction.Its main content is: examines the n-hepta ne isomerization reaction on the Ni Ce/SAPO-11 catalyst.The results showed that the best Ni load was 4%(w),the best w(Ni):w(Ce)=1:1,optimal load order:first load Ce.The best red uction conditions:v(H2)=60mi/min,T=480℃,t=5h.To optimize the isomerization process by r esponse surface analysis software Design-Expert.Determine the optimum process as follow-s:T=315℃,WHSV=4h-1, n(H2)/n(C7)=1.34.Under the optimum process conditions,n-heptan e isomerization conversion and iso-heptane selective reached 32.27% and 63.17%.