Effect of zeolite amount on the properties of Pt/(AlSBA-15 + Beta zeolite) micro-mesoporous catalysts for the hydroisomerization of n-heptane

• Published in: Fuel (Guildford) Vol. 280; p. 118607
• Main Authors: Fedyna, Monika, Śliwa, Michał, Jaroszewska, Karolina, Trawczyński, Janusz
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.11.2020; Elsevier BV
• Subjects: Acidity; Beta zeolite; Catalysts; Chemisorption; Composite materials; Heptanes; Hydroisomerization; Micro-mesoporous materials; N-heptane; NMR spectroscopy; Octane number; Physicochemical properties; Platinum catalyst; Properties (attributes); Synthesis; Zeolites; Beta zeolite; N-heptane; Hydroisomerization; Micro-mesoporous materials; Platinum catalyst; Octane number
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2020.118607

[Display omitted] •Micro-mesoporous AlSBA-15 + Beta composites were synthesized by one-step method.•Pt/AlSBA-15 + Beta catalysts designed for n-heptane isomerization.•Pt/AlSBA-15 + Beta (with 14 or 25% of Beta) showed the highest isomerization selectivity.•Isomerization factor (IF) predicting the isomerization performance was proposed. The composite (AlSBA-15 + Beta zeolite) materials were prepared using a simple one-step hydrothermal synthesis, aiming to investigate the effect of the ratio AlSBA-15 : zeolite on their physicochemical properties. The resulting micro-mesoporous materials (SBB) containing from 14 to 25 wt% of zeolite were used as supports for Pt catalysts in hydroisomerization of n- heptane (n-C7). Obtained catalysts were characterized by means of nitrogen sorption, XRD, Py–IR, 27Al MAS NMR, CO chemisorption, TEM and SEM. It was found, that the textural properties of the micro-mesoporous materials were comparable to pure AlSBA-15. It also appeared that the introduction of zeolite into AlSBA-15 at the synthesis stage affected the total acidity of the composite materials. Both the total acidity and strength of acid sites depended on AlSBA-15: zeolite ratio. The results of n-C7 hydroconversion showed that catalysts containing 14 and 25 wt% of zeolite provided the highest yield of the most desired, high-octane number products. The most promising Pt/AlSBA-15 + BEA catalysts (i.e. containing 14 and 25 wt% of Beta) allows to improve research octane number from 0 to the 65–70 points.