Different Si/Al SAPO-11 were synthesied in short crystallizing time under hydrothermal condition with diethylamine as template. XRD spectra show that crystallinity and SAPO-11 size decrease with increasing Si/Al ratio. ~(29)Si NMR spectra indicate that SAPO-11 sample with an Si/Al of 0.33 significantly enhances the neighboring region between SAPO region and Si region, and NH_3-TPD results also show it has higher strong acid/weak acid ratio. Impregnated by Pd, the Si/Al 0.33 sample with enhanced neighboring region has the highest n- dodecane hydroisomerization conversion and selectivity.

Key words: DIETHYLAMINE, TEMPLATE AGENT, C12 COMPOUNDS, HYDROGENATION, ISOMERIZATION, SELECTIVITY