Hydroisomerization of n-hexadecane on Pt-containing silicone aluminum phosphate molecular sieves SAPO-11 with different silicon content

Objectives. To obtain silicone aluminum phosphate molecular sieves SAPO-11 with different silicon content, to determine their pore space and acidic properties, to apply 0.5 wt % to their surface Pt, and to evaluate the effectiveness of the use of n-hexadecane in the hydroisomerization reaction.

Methods. The chemical composition of the SAPO-11 molecular sieves obtained was determined by means of X-ray fluorescence spectroscopy using a Shimadzu EDX-7000P device. The radiographs of non-calcined SAPO-11 were recorded on a Shimadzu XRD-7000 diffractometer in CuKα radiation.

Results. Silicone aluminum phosphate molecular sieves SAPO-11 containing 0.5 wt % Pt on the surface were obtained from gels. As the SiO₂/Al₂O₃ ratio increases, the number of acid centers increases. This then leads to an increase in the conversion of n-hexadecane. The selectivity of the formation of hydrocarbons of the structure decreases at the same time.

Conclusions. Silicone aluminum phosphate molecular sieves Pt-SAPO-11 were obtained. It was also found that the samples undergo n-hexadecane conversion.

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