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NH 4 -SSZ-13 is etched with an aqueous solution of 40 w /% NH 4 F under different time/temperature conditions to obtain hierarchical derivatives. The etched zeolites are characterized by XRD, SEM, N 2 physisorption, 29Si/27Al/19F MAS NMR, ICP-AES, and their acidity monitored by in situ FTIR spectroscopy using acetonitrile as a probe molecule. The results highlight that the zeolite is very sensitive to high temperature and high liquid-solid ratio treatments leading to substantial crystallinity losses. These two parameters need careful tuning to obtain hierarchical derivatives retaining important characteristics as micropore volume and framework Si/Al ratio. The catalytic activity of the modified SSZ-13 is evaluated in the n-propanol conversion. Image 1 • Zeolite SSZ-13 (CHA-type) is subjected to chemical etching in an aqueous NH 4 F solution to introduce mesopores. • The hierarchical zeolite preserved the parent zeolite properties in terms of framework composition and Brønsted acidity. • The obtained SSZ-13 derivatives show higher coke contents but slower deactivation in the dehydration of n-propanol. [ABSTRACT FROM AUTHOR]

[Display omitted] • Elucidation of the promotion with antimony and tin on iron catalysts. • 7–10 times increase in the intrinsic activity of iron surface sites. • In-situ identification of the structure of working catalysts. • Strong interaction of the promoters and iron active phase. • Iron antimony bimetallic nanoparticles in activated catalysts. Fischer-Tropsch synthesis provides an important opportunity for utilization of biomass and plastic waste. Iron catalysts are the catalysts of choice for light olefin synthesis using Fischer-Tropsch reaction. In this paper, we investigate strong promoting effects of antimony and tin on the catalytic performance of silica supported iron Fischer-Tropsch catalysts using a combination of advanced and in-situ techniques. The catalyst doping with these elements added via impregnation results in a major increase in the reaction rate and much better catalyst stability. No enhancement of iron dispersion was observed after the promotion, while somewhat higher extent of iron carbidization was observed in the antimony promoted catalysts. Iron-bismuth bimetallic nanoparticles are detected by several techniques. In the working catalysts, the promoters are located in close proximity to the iron nanoparticles. The promotion leads to the 7–10 times increase in the intrinsic activity of iron surface sites due to their interaction with the promoters. [ABSTRACT FROM AUTHOR]