Development of Pt/Zeolite for Selective Conversion of n-Decane and n-Dodecane to i-C6-7 and i-C7-9

Jet fuel production from long-chain n-paraffins obtained by hydroprocessing of vegetable oils and animal fats has attracted immense interest. Isomerization and mild cracking are essential to transform long-chain n-paraffins with chain lengths of 16, 18, or 20 into bio-jet fuels consisting of isoparaffins with carbon numbers ranging from 9 to 15. Bifunctional catalysts consisting of noble metal and metal oxide support with solid acid, such as Pt loaded zeolite, are promising for hydroisomerization and cracking reactions. However, the effect of the specific properties of Pt loaded zeolite on the hydroisomerization and simultaneous mild cracking activity are not understood. We investigated the hydroisomerization and cracking of n-paraffins into isoparaffins with shorter chain length by 3-5 carbons over Pt loaded zeolite. n-Decane was first used as a reactant to simplify the reactions, and the effects of zeolite framework structure, solid acid sites, and Pt loading were investigated. 0.5 wt% Pt loaded MFI with Si/Al of 200 was found to maximize the targeted isoparaffin yield. Further modification of the optimized catalyst was performed for isoparaffin production from n-dodecane. Addition of MgO to the catalyst successfully suppressed overcracking and improved the desired isoparaffin yield.