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Abstract The pillared MWW (PMWW or MCM-36) and pillared MFI (PMFI) are two prominent representatives of meso-/microporous lamellar zeolites, which are made by pillaring of layered MCM-22(P) and multilamellar MFI precursors, respectively. They both consist of a 10-membered ring sinusoidal micropore channel within each zeolitic layer and mesopore voids created by pillars between two adjacent zeolitic layers. Although catalytic activities of PMWW and PMFI have been compared, identification of mesopore differences between these two pillared lamellar zeolites has not been attempted. In this work, we report the differences in mesopore characteristics between PMWW and PMFI zeolites probed by atomic layer deposition (ALD) of titania (ALD-TiO 2) species and a combination of structural, textural, composition and catalytic property analyses of the samples before and after ALD treatment, respectively. The results suggest PMFI has cylindrical mesopores with uniform sizes from pore entrance to main body, while PMWW has ink-bottle mesopores with the neck size much smaller than pore body. The communication between micropore and mesopore in PMFI is direct, but no communication exists in PMWW zeolites. The ALD-TiO 2 process considerably modified external surface composition of PMFI and PMWW zeolites, which consequently led to a new application of the pillared lamellar zeolite materials, i.e., photo-catalytically active meso-/microporous zeolites for environmental remedy reactions. Graphical abstract Image 1 Highlights • Identification of mesopore differences between PMFI and PMWW was attempted. • Atomic layer deposition of titania was used as probe for mesopore differences. • PMFI has more uniform mesopores compared to PMWW zeolite. • Atomic layer deposition of titania enabled photocatalytic activity. [ABSTRACT FROM AUTHOR]

Lamellar MFI zeolite and lamellar MFI zeolite supported nickel were synthesized and examined for ex-situ catalytic upgrading of the vapors (without using any fluidized gases such as N 2 and H 2) resulted from fast pyrolysis of wood chips in comparison to its commercial MFI zeolite and its supported nickel counterparts. Pyrolysis tests were carried out using a catalytic augur reactor at atmospheric pressure, while pyrolysis unit was operating at 450 °C and upgrading unit at 420 °C, respectively. The introduction of nickel with a high dispersion over the zeolitic supports caused a significant increase in the products of aromatic compounds. Moreover, the addition of nickel to zeolite supports changed their acidity and decreased the total number of acid sites and the ratio of Brønsted to Lewis acid sites as determined by pyridine-FTIR spectroscopy. The use of lamellar zeolite catalysts increased the efficiency of catalytic cracking of pyrolysis vapors and their modification with nickel helped tuning the Lewis acidity to further increase catalytic cracking which resulted in a higher yield of the low molecular weight aromatics present in the bio-oil. • Lamellar catalysts are synthesized and extensively characterized. • Ex-situ catalytic fast pyrolysis without fluidizing gas can lead to a low bio-oil deoxygenation. • Lamellar catalysts are found to enhance catalytic cracking of pyrolysis oil vapors. • Lamellar catalysts show no loss in activity after multiple uses. [ABSTRACT FROM AUTHOR]

• Characteristics of the coke deposits on lamellar metal (Ga or Zn)-modified zeolites were studied. • Mesoporous lamellar structure decreases the coke formation by facilitating the external coke deposition. • Metal modification decreases the coke formation by changing the acidity of zeolite. • Highest fraction of light coke is obtained for Zn-modified lamellar zeolite. • Both zeolite structure and metal-modified acidity affect the coke formation. The effects of meso-/microporous structure and metal-additive (Ga or Zn) of lamellar MFI catalysts on the characteristics of coke deposits during ethylene-to-aromatic liquids conversion were investigated. The nature, composition, and location of coke deposits in spent lamellar catalysts were analyzed and compared to those on the microporous MFI counterparts, using FTIR, UV–Vis, GC–MS, and argon adsorption-desorption. The total amount of coke and the changes in coke nature during catalyst regeneration were studied by MS/FTIR combined with temperature programmed oxidation. The lamellar meso-/microporous structure of MFI reduces the coke quantity and the heavy coke fractions. The coke preferentially deposites on external surface of lamellar zeolite due to the lower diffusion limitation for bulky coke precursors. Metal-additive changes the catalyst acidity and decreases the coke formation rate, especially when zinc is used. Therefore, the coke formation on zeolite can be tuned by modulating the textural and acidity properties of the metal-modified catalyst. [ABSTRACT FROM AUTHOR]

• Catalytic performance of metal (Ga or Zn)-loaded mesoporous lamellar zeolites was evaluated. • Mesoporous lamellar structure is pivotal in determining metal dispersion in zeolite catalyst. • Metal loading changes the acidity of the zeolite catalyst and effect of Zn is more pronounced compared to Ga. • Higher liquid aromatics yield and selectivity for mono-benzene alkylated aromatics was observed while less coke was formed. • Both zeolite structure (mesoporosity) and type of metal dopant affect the catalytic performance of catalyst. The effects of meso-/microporous structure and metal-modification with gallium or zinc on catalytic performances of lamellar MFI zeolites in ethylene conversion reaction to liquid aromatics were investigated. TEM, XRD, Ar adsorption-desorption, UV-Visible spectroscopy, and H 2 -TPR measurements showed that the zeolite structure is a pivotal factor for controlling the type of metal dopant species forming on zeolite, their size, and their distribution. Adding metal dopants to zeolite structure decreased the Brønsted to Lewis (B/L) acid site ratio in the zeolites and improved their catalytic performance. As a result, metal-modified lamellar MFI zeolites showed higher liquid aromatics yield and selectivity for mono-benzene alkylated aromatics and lower coke formation rate compared to their microporous commercial MFI analogies. Zinc-loaded lamellar MFI had the most efficient catalytic performance among all studied catalysts. This phenomenon can be explained by higher accessibility of reactants to active sites and facilitated transport of products from lamellar structure of this zeolite and the low B/L acid site ratio of this catalyst provided by metal-modification, which is more suitable for ethylene aromatization. A bifunctional reaction mechanism has been proposed based on the analysis results of reaction product distributions that demonstrates the effect of both zeolite acid sites and metal sites in conversion of ethylene to liquid aromatics over MFI zeolite catalysts. [ABSTRACT FROM AUTHOR]