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To enhance the gasoline octane number, low-octane linear n-alkanes should be converted into their high-octane di-branched isomers via n-alkane hydroisomerization. Therefore, hierarchical SAPO-11-based catalysts are prepared by adding different contents of sodium dodecylbenzene sulfonate (SDBS), and they are applied in n-nonane hydroisomerization. When n(SDBS)/n(SiO2) is less than or equal to 0.125, the synthesized hierarchical molecular sieves are all pure SAPO-11, and as the SDBS content increases, the submicron particle size decreases, and the external surface area (ESA) increases. Additionally, these hierarchical SAPO-11 have smaller submicron particles and higher ESA values than conventional SAPO-11. When n(SDBS)/n(SiO2) is greater than 0.125, with increasing SDBS content (n(SDBS)/n(SiO2) = 0.25), the synthesized SAPO-11 contains amorphous materials, which leads to a decline in the ESA; with the further increase in SDBS content (n(SDBS)/n(SiO2) = 0.5), the products are all amorphous materials. These results indicate that in the case of n(SDBS)/n(SiO2) = 0.125, the synthesized SAPO-11 molecular sieve (S–S3) has the most external Brønsted acid centers and the highest ESA of these SAPO-11, and these advantages favor generation of the di-branched isomers in hydrocarbon hydroisomerization. Among these Pt/SAPO-11 catalysts, Pt/S–S3 displays the highest selectivity to entire isomers (83.4%), the highest selectivity to di-branched isomers (28.1%) and the minimum hydrocracking selectivity (15.7%) in n-nonane hydroisomerization.

with (NH 4 ) 2 SO 4 and subsequent calcination. Compared with the physical mixture of SO 4 2− /ZrO 2 and conventional SAPO-11 (SZ+SA-11), SZ@SA-11 possesses smaller ZrO 2 particles and more tetragonal ZrO 2 . Moderate and strong Brønsted acid sites (MSBAS) are produced only via interactions between tetragonal ZrO 2 and sulfate, so SZ@ SA-11 with more tetragonal ZrO 2 has a greater amount of MSBAS than SZ+SA-11.

Ni(MoS4)2(C13H30N)2 was synthesized and adopted for preparing a NiMoS/γ-Al2O3 hydrodesulfurization catalyst, and the as-prepared catalyst exhibits superior 4,6-dimethyldibenzothiophene hydrodesulfurization activity.