Catalytic conversion of n-butane over Au-Zn-modified nano-sized HZSM-5

An Au-Zn-modified HZSM-5 catalyst was prepared using deposition-precipitation and wet impregnation methods. To obtain a better understanding of the relationship between catalyst characteristics and catalytic performance, a thorough study of various catalyst samples (HZSM-5, Au/HZSM-5, Zn/HZSM-5, and Au-Zn/HZSM-5) was performed. The interactions between Au and Zn species in Au-Zn/HZSM-5 were determined using ultraviolet-visible and X-ray photoelectron spectroscopies. Compared with Zn/HZSM-5, the introduction of Au to give Au-Zn/HZSM-5 effectively promotes the dehydrogenation and aromatization of n-butane, and also suppresses hydrogenolysis over Zn species. The n-butane conversion (70.8%) and selectivity for olefins and aromatics (61.98%) increased significantly. The dry gas selectivity also decreased significantly to 28.4%. Au-Zn-containing HZSM-5 is a useful catalyst for the conversion of light alkanes. (c) 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.