Crystallization-Driven Ni Nanoparticle Redispersion Unlocks Metal–Acid Synergy in Long-Chain Alkane Isomerization

Long-chain alkane hydroisomerization constitutes an essential catalytic transformation within the petroleum refining process, enabling the production of high-performance, environmentally benign fuels and lubricants. Although Ni-based catalysts offer economic advantages compared to platinum analogues, their industrial application is limited by inferior metal dispersion and susceptibility to sintering. This study demonstrates an in situ recrystallization strategy to fabricate *MRE zeolite-supported Ni catalysts with precisely modulated metal distribution and tailored reducibility. The optimized catalyst achieves an isomer yield of 87.3% in n-dodecane hydroisomerization. This performance surpasses all documented Ni-based systems and demonstrates parity with benchmark Pt catalysts while sustaining operational stability over 1000 h. Characterization techniques, including STEM, in situ DRIFT spectroscopy, and EXAFS, reveal that the dynamic redistribution of Ni species occurs during zeolite crystallization, facilitated by organic structure-directing agents. Simultaneously, the recrystallization process effectively isolates active silicon precursors from Ni, thereby minimizing the formation of inert nickel phases. Furthermore, the formation of Ni–O–Si structures has been shown to enhance the metal dispersion stability. This crystallization-driven metal redispersion strategy provides a paradigm for the rational design of metal–zeolite bifunctional catalysts.