In this paper, the catalytic properties of novel granulated hierarchical (micro-meso-macroporous) zeolites H-Yh and H-ZSM-5h in the reaction of aniline and bio-1,2-propanediol are investigated. The influence of shape selectivity, textural and acid characteristics of zeolites on their activity and selectivity in the above reaction is shown. For the first time it was established that zeolite H-Yh was the most effective for obtaining 2-methyl-3-npropyl-1H-indole 1 (yield 52 %), while 3,4-dimethyl-1-phenyl-1H-pyrrole 2 was obtained predominantly over zeolite H-ZSM-5h (yield 54 %). The conditions for compounds 1 and 2 with the maximum yield were determined. Possible pathways of the obtaining products are proposed, with consideration to the type, concentration and strength of acid sites, as well as the structural features of zeolites.

Amorphous mesoporous materials are promising as catalysts for processes involving or forming bulk molecules. In a reaction such as acetone condensation to form mesitylene, an effective catalyst should not only have a developed porous structure but also have active centers of acidic and basic types. The sol–gel approach allows one to obtain titanosilicates with such characteristics. This work demonstrates the possibility of controlling their properties by varying the conditions for the synthesis of titanosilicate gels. It has been established that controlling hydrolysis allows one to increase the activity of amorphous mesoporous titanosilicates by 10 times: from acetone conversion of 6% to 60%. It has been shown that the use of titanium acetylacetonate complexes in the synthesis of gels leads to an increase in the content of tetracoordinated Ti in the structure and contributes to an increase in the acidity of titanosilicates. During the condensation of acetone on the obtained mesoporous titanosilicates, high acetone conversion (60–79%) and mesitylene selectivity of up to 83% were achieved.

The physicochemical properties of a series of catalysts based on granulated Na-Yh zeolite with the hierarchic (micro–meso–macro) pore structure (Na-Yh, HNa-Yh, MgO/Na-Yh, La2O3/Na-Yh, TiO2/Na-Yh) and the activity and selectivity of these catalysts in isophorone aromatization were studied. MgO/Na-Yh and La2O3/Na-Yh zeolites with high content of basic sites and low content of Brønsted acid sites are the most effective in the synthesis of 3,5-dimethylphenol: The 3,5-dimethylphenol formation selectivity reaches 63–69

The study investigates the catalytic performance of hierarchical granular Na–Yh zeolites promoted with metal oxides (designated as ZnO/Na–Yh, NiO/Na–Yh, Co3O4/Na–Yh, and CuO/Na–Yh) in the synthesis of quinolines from aniline and n-propanol. The highest aniline conversion and highest total quinoline selectivity (49 and 63

The catalytic properties of zeolites (microporous H-Y and granular micro-mesomacroporous H-Y h ) and amorphous mesoporous aluminosilicate ASM in the reaction of 1,2-phenylenediamine with acetone were studied. The main reaction product was 2,2,4-trimethyl-2,3-dihydro-1 H -1,5-benzodiazepine (selectivity up to 99% at a 94% conversion of 1,2-phenylenediamine). For the synthesis of 1,5-benzodiazepine, the most effective was 0.95H-Y h , a granular zeolite with a hierarchical porous structure. The catalyst demonstrated operational stability for three cycles.

The study investigates the catalytic performance of microporous and granular micro–meso–macroporous zeolites (H-ZSM-5 and H-ZSM-5h, respectively) in synthesis of quinolines by the reaction of 2-aminoacetophenone with diketones (2,4-pentanedione or dimedone), known as the Friedländer synthesis. In the presence of H-ZSM-5h, 1-(2,4-dimethylquinolin-3-yl)ethanone ( 1a ) and 3,4-dihydro-3,3,9-trimethyl-1(2 H )-acridinone ( 1b ) were produced in 82 and 93% yields, respectively.

Samples of SAPO-11 silicoaluminophosphate zeolites crystallized from silicoaluminophosphate gels with various SiO2/Al2O3 ratios were studied using X-ray fluorescence and X-ray diffraction analysis, scanning electron microscopy, N2 adsorption–desorption, NH3-TPD, and IR spectroscopy of adsorbed pyridine. With an increase in the SiO2/Al2O3 ratio, the crystallinity of the samples diminishes, the sizes of primary crystals decrease and their external specific surface rises, and the concentration of acid sites in the molecular sieve passes through a maximum. The prepared samples of SAPO-11 were examined during oligomerization of α-methylstyrene into dimers. It was found that the maximum values of monomer conversion and selectivity for linear α-dimers are detected when using a silicoaluminophosphate sample possessing the highest concentration of acid sites and a smaller crystal size.

The catalytic properties of a microporous H-ZSM-5 zeolite and a granular hierarchical H-ZSM-5 h zeolite in the synthesis of basic pyridines and quinolines have been studied. A specific feature of zeolite H-ZSM-5 h is the absence of a binder in the granules and the presence of micro-, meso-, and macropores in the pore structure. The H-ZSM-5 h sample comprises, in addition to crystals of the original zeolite, crystals with a size of 15–100 nm. The H-ZSM-5 h sample exhibits a higher activity, selectivity, and stability than those of the microporous H-ZSM-5 zeolite in all studied reactions.

The activity, selectivity, and stability of microporous highly dispersed zeolites (H-Y, H-ZSM-5) and granulated hierarchical zeolites (H-Y-h and H-ZSM-5(h)) were studied in the synthesis of quinolines by the Skraup reaction. Texture, porous structure, morphology of crystals, acidic properties were characterized by XRD, XRF, N-2 adsorption-desorption, SEM, NH3-TPD methods. It was found that quinoline, 2- and 4-methylquinolines are the main products in the reaction of aniline with glycerol in the presence of the studied catalysts. H-ZSM-5(h) and H-Y-h catalysts are more efficient than catalysts H-ZSM-5 and HY and provide a yield of quinolines to 72.4 (H-ZSM-5(h)) and 60.2 % (H-Y-h) at 450 degrees C, 0.2 h(-1), the molar ratio of aniline:glycerol=1 : 3. The high activity and selectivity of hierarchical zeolites are due to the presence of meso- and macropores, as well as nanocrystals of 15-100 nm size. It was reported that hierarchical catalysts exhibit higher stability in the reaction compared with microporous zeolites.

The study investigates the catalytic performance of microporous (H–Y) and micro–meso–macroporous (H–Yh, Fe2O3/H–Yh, PbO/H–Yh, and La–H–Yh ) FAU-type zeolites in the condensation of acetone with ammonia. In the presence of H–Yh, Fe2O3/H–Yh, and La–H–Yh, 2,4,6-trimethylpyridine was synthesized with selectivity of 54%, 58%, and 24%, respectively. In the presence of H–Y and PbO/H–Yh, the predominant reaction was acetone condensation, with the reaction products mostly consisting of diacetone alcohol and mesityl oxide.

Various methods, such as XRF, XRD, SEM, N 2 adsorption/desorption, NH 3 –TPD, and IR spectroscopy of adsorbed pyridine, were used to characterize SAPO-11 samples crystallized from Al-isopropoxide as an aluminum source and from SiO 2 with various dispersions (4, 22, and 200 nm) as a silicon source. Decreasing the size of SiO 2 particles was shown to enhance the total concentration of acid sites and to affect the morphology and increase the dispersion of the primary crystals. These SAPO-11 samples were then tested in the oligomerization of α-methylstyrene into its valuable dimers. The SAPO sample synthesized using a SiO 2 sol with an average particle size of 4 nm exhibited a higher concentration of strong acid sites and higher accessibility of those sites than the other tested samples. These advantages allowed this SAPO sample to achieve the highest monomer conversion and the highest α-methylstyrene dimer selectivity.

The study investigates the catalytic properties of microporous (H–Y) and micro-meso-macroporous (H–Y-mmm) FAU-type zeolites in the synthesis of 2-methyl-5-ethylpyridine (MEP) by the reaction of acetaldehyde with ammonia. At 150°C, an acetaldehyde to ammonia molar ratio of 1 : 3, and a catalyst content of 10 wt %, a MEP yield of 58% (0.95H–Y) and 63% (0.95H–Y-mmm) was achieved with a MEP selectivity of 91 and 93%, respectively. The examination of the catalyst stability revealed that hierarchical H–Y-mmm zeolites ensure a 100% MEP selectivity during 4–5 cycles with a slight decline in the catalytic activity, while H–Y zeolites are active during the first cycle only.

The oligomerization of 1-pentene is an efficient process for producing environmentally friendly high-quality fuel components. The catalytic properties of FAU, OFF, MOR, BEA, MTW, and MFI zeolites in the H form are studied in the synthesis of pentene oligomers in an autoclave at 110–200°C. It is established that the high activity of H-Y and H-Beta(18) zeolites in the reaction of oligomerization, where the yield of oligomers reaches 97–100%, is determined by their wide-pore structure and high concentration of acid sites. The oligomers prepared on these catalysts are 30–73% dimers, 25–50% trimers, and 2–14% oligomers, with number n > 3 of monomer units. Narrow-pore zeolites (H-ZSM-5) or zeolites with one- and two-dimensional channel systems (H-OFF, H-MOR, and H-ZSM-12) are less active in the oligomerization of 1-pentene, with decenes as the main products of the reaction.

The study of isoamylene oligomerization over a number of microporous zeolitessuch as H–Y, H–MOR, H–Beta, H–ZSM-12, and H–ZSM-5 revealed that the isoamyleneconversion rate decreases in the following order: H–MOR > H–Y > H–Beta-40>> H–ZSM-12 > H–ZSM-5. The maximum yields of isoamylene oligomers wereachieved by using H–MOR (85.0%), H–Y (80.1%), and H–Beta-40 (79.8%). Thepredominant isoamylene oligomers are dimers regardless of the zeolite catalystused. The trimer yield reaches its highest when wide-pore zeolites like H–MOR,H–Y, or H–Beta-40 are employed. An increase in the number of acid sites enhancesmonomer conversion rate, oligomer yield, and oligomer molecular weight.Conditions for producing isopentene dimers and trimers with the maximum possibleyield were determined.

The catalytic activity of micro- and micro–meso–macroporous zeolites of the FAU structural type and an ASM mesoporous aluminosilicate in the reaction of aniline with C3–C5 aldehydes has been studied. It has been established that under the studied conditions, (2S, 3S, 4R)-2,3-dialkyl-N-phenyl-1,2,3,4-tetrahydro-4-quinolinamines are the main products formed over the tested catalysts with the selectivity of up to 71%.