{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T08:25:53Z","timestamp":1787214353981,"version":"build-2736575974"},"reference-count":32,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T00:00:00Z","timestamp":1787184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IPC UFRC RAS","award":["FMRS-2024-0012"],"award-info":[{"award-number":["FMRS-2024-0012"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The morphology and pore structure of ZSM-48 zeolite are critical parameters determining the catalytic performance of bifunctional catalysts in the hydroisomerization of long-chain n-paraffins. This study investigates the effects of the Na2O\/SiO2 molar ratio (0.02\u20130.12) in the synthesis gel and hydrothermal treatment duration (48\u201372 h) on the crystallization kinetics, phase purity, and physicochemical properties of ZSM-48. Low alkalinity (Na2O\/SiO2 = 0.04\u20130.06) and shorter synthesis times (48 h) promote the formation of small aggregates composed of short needle-like crystals with enhanced intercrystalline mesoporosity. Conversely, increasing the alkalinity and crystallization duration accelerates crystal growth, resulting in dense pseudo-spherical aggregates (up to 4\u20137 \u03bcm in size) with restricted external surface area and increased diffusion limitations. Catalytic testing of Pt\/ZSM-48 (0.5 wt.% Pt) in n-hexadecane hydroisomerization demonstrates that crystal morphology, size, and porosity significantly influence process selectivity. The catalyst based on nanosized ZSM-48 (Pt\/Z48-06-2) effectively mitigates diffusion resistance, yielding a maximum isomer yield of 73% at 82% selectivity. In contrast, larger, densely packed aggregates with high but poorly accessible acidity intensify secondary hydrocracking reactions, reducing a maximum isomer yield to 46%. These results highlight the ability to tune the catalytic properties of ZSM-48 through careful control over gel alkalinity and crystallization kinetics.<\/jats:p>","DOI":"10.3390\/molecules31162900","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T08:10:20Z","timestamp":1787213420000},"page":"2900","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Alkali Content as a Tool for Tailoring ZSM-48 Physicochemical Properties: From Crystallization Kinetics to Catalytic Performance in n-Hexadecane Hydroisomerization"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6601-390X","authenticated-orcid":false,"given":"Dmitry V.","family":"Serebrennikov","sequence":"first","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-8468-0434","authenticated-orcid":false,"given":"Arthur I.","family":"Malunov","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arthur R.","family":"Zabirov","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8994-3456","authenticated-orcid":false,"given":"Nadezhda A.","family":"Filippova","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra D.","family":"Zimina","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfira N.","family":"Khazipova","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ekaterina S.","family":"Mescheryakova","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3466-3104","authenticated-orcid":false,"given":"Rufina A.","family":"Zilberg","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Ufa University of Science and Technology, 450076 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marat R.","family":"Agliullin","sequence":"additional","affiliation":[{"name":"Institute of Petrochemistry and Catalysis, Ufa Federal Research Centre of the Russian Academy of Sciences, 450075 Ufa, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"790","DOI":"10.1007\/s10553-022-01452-x","article-title":"Diesel fuel for use in Arctic and Subtropical Climates","volume":"58","author":"Karpov","year":"2022","journal-title":"Chem. 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