ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Preparation of Pd/Al2O3@silicalite-1 core–shell beads and their application to hydrogenation reactions

Tong Zhang, Zu-Qiang Zhang, Lu Lin, Si Li, Xin-Juan Yan, Hai-Ou Liu, and Xiong-Fu Zhang

State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, China

E-mail: xfzhang@dlut.edu.cn

Abstract: Core-shell composite beads comprising a Pd-loaded Al₂O₃ core and a shell of inter-grown silicalite-1 (siliceous ZSM-5) crystals were synthesised. The incompatibility between the Pd/Al₂O₃ core and the zeolite shell was circumvented by a layer-by-layer self-assembly of polyelectrolyte to adsorb nanosized silicalite-1 seeds onto the core surface, followed by a secondary solvo-thermal treatment to form the continuous and well-intergrown silicalite-1 shell. The thickness of the outer zeolite shell could be tuned by monitoring the secondary growth time. When employed as catalyst for the hydrogenation reaction of alkenes to explore its full potential use, the Pd/Al₂O₃@silicalite-1 core-shell catalyst exhibited excellent size-selectivity, poison-resistance and leaching-proof properties. Such a catalyst@zeolite core-shell structure is expected to find promising applications in heterogeneous catalysis and adsorption.

Keywords: core-shell structure – Pd/Al2O3 catalyst – silicalite-1 zeolite – hydrogenation

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0181

Chemical Papers 69 (12) 1556–1562 (2015)