Study on the transformation rule of n-tetradecane hydroisomerization over modified Pt/SAPO-11 catalyst

Pt/SAPO-11 bifunctional catalyst was modified with citric acid and carbon black.The effects of different modified methods on the catalytic activity of Pt/SAPO-11 catalysts were investigated using n-tetradecane as the probe reaction.Results indicated that the isomerization products were mainly composed of monomethyl isomer, the modification has not changed the acid strength of the catalyst, but the acid concentration has decreased.The citric acid significantly improved the low temperature catalytic activity of the catalysts, while carbon black effectively promoted the mass transfer performance and monomethyl isomer selectivity of the catalysts.The cracking products were mainly composed of C₆ compounds, and modification did not change the shape selective effects of SAPO-11 molecular sieve.Carbon number distribution of cracking products was obvious asymmetric distribution.