Balancing Acid and Diffusion Properties in Hierarchical Catalysts for Efficient Selective Hydrogenation of Oleic Acid

ABSTRACT Hierarchical Ni/ZSM‐22‐SBA‐15 meso‐microporous catalysts (Ni/ZS‐x) with different acid properties and diffusion characteristics (acid‐diffusion) properties were synthesized successfully and applied to the production of high‐quality jet fuel by the efficient one‐step hydrogenation (hydrodeoxygenation, isomerization, and cracking) of oleic acid. The acid‐diffusion properties of the catalysts are modulated by tuning the ZSM‐22 seed content, and their effects on the hydrogenation reactions were investigated. Acid properties affect the extent of isomerization and cleavage reactions, whereas diffusion properties affect the accessibility of active centers. The balanced acid‐diffusion properties are conducive to efficient hydrogenation reactions of oleic acid. The optimal Ni/ZS‐3 exhibits the highest jet fuel yield (56.3%, 340°C) and superior iso/n ‐alkane ratio ( i / n = 3.12) because of its well‐balanced acid‐diffusion properties. Besides, the possible hydrogenation mechanism of oleic acid is proposed.