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SBA-15, possessing uniform mesopore system and large specific surface area, shows a tremendous mass transfer advantage in the reactions involving reactant, intermediate or product whose dynamic diameter is larger than the pore size of microporous zeolites, but the low acidity greatly limits its application in acid-catalyzed reactions (e.g., hydroisomerization). Herein, we report an Al-functionalized SBA-15 molecular sieve (Al-SBA-15) with enhanced acidity obtained via a pH-adjusted prehydrolysis synthesis approach for hydroisomerization. Its physicochemical properties and catalytic performance were carefully characterized, evaluated in hydroisomerization of n-octane after loading active component Pt, and compared with a pure silica SBA-15 and two Al-containing samples (AlSBA-15 and Al/SBA-15) produced through direct synthesis and wetness impregnation, respectively. The results show that the acidity of three Al-functionalized samples is prominently improved, and thus the conversion of n-octane over them is greatly increased when compared with siliceous SBA-15. Moreover, among three Al-containing SBA-15 materials, Al-SBA-15 with the largest pore diameter and moderate acidity exhibits relatively high n-octane conversion and di-branched isomers selectivity but minimal cracking selectivity. These results demonstrate that pH-adjusted prehydrolysis is an effective route to preparing Al-functionalized SBA-15 with suitable acidity for the hydroisomerization of alkanes. Unlabelled Image • Three Al-functionalized SBA-15 materials were prepared by using different methods. • The acidity is greatly improved after introducing Al into the siliceous SBA-15. • Al-SBA-15 prepared via pH-adjusted prehydrolysis has suitable pores and acidity. • Al-SBA-15 shows good catalytic performance in n-octane hydrosiomerization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ball-milling process is used to prepare optimal NiP-Hβ/KL catalyst. • Modified Kaolin acts as a spacer to dilute the strong acidity of NiP-Hβ. • Mesopores in KL provides more activity sites for producing di-branched products. • NiP-Hβ/KL exhibits high conversion, high selectivity, and liquid yield. Isomerization of alkane is one of the most important catalytic processes for producing environmentally friendly gasoline fraction with high octane number. However, the development of non-noble metal based catalysts with high conversion and selectivity towards multi-branched isomerized products is still challenging. Herein, we report that a NiP-Hβ/modified Kaolin catalyst was successfully prepared by ball-milling of amorphous NiP nanoparticles with Hβ/modified Kaolin composites and applied for n-hexane isomerization. The introduction of chemically modified Kaolin with abundant weak-medium acid sites and mesopores not only alleviates the cracking of isomerized products on the strong acid sites on Hβ, but also provides more active sites for the formation of di-branched isomerized products with high octane number. As a result, the NiP-Hβ/modified Kaolin catalyst shows an excellent catalytic performance for n-hexane isomerization in terms of good conversion (78.1%), high selectivity towards mono-branched (75.4%) and di-branched (21.4%) i-C 6 products, and high liquid yield (99.9%). This work paves the way to the development of high performance non-noble metal based catalysts for large scale production of clean gasoline. [ABSTRACT FROM AUTHOR]

• The surface chemistry of mesoporous carbons is tuned using different oxidants. • The acidity and oxygen-containing groups of adsorbents affect ADN performance. • The adsorption mechanism between the carbon adsorbents and NCCs is revealed. • The optimal adsorbent exhibits an excellent ADN performance in real diesel. Mesoporous carbons are widely utilized as adsorbents for adsorptive removal of nitrogen-containing compounds in fuel. Herein, hollow mesoporous carbon nanospheres (HMCNs) were successfully synthesized via a facile silica-assisted sol–gel strategy and further oxidized by different acids (HNO 3 , H 2 SO 4 , and (NH 4) 2 S 2 O 8) to adjust their surface chemistry. The HMCNs oxidized with (NH 4) 2 S 2 O 8 contain the most oxygen-containing groups and exhibit the strongest acidity, resulting in high adsorption capacities towards quinoline (QUI, 29.78 mg N ·g−1) and indole (IND, 26.59 mg N ·g−1) in model fuel. The superior performance is attributed to the acid-base interaction and hydrogen bonding interaction between the adsorbent and QUI/IND molecules. Remarkably, the adsorption capacity towards nitrogen-containing compounds in real diesel is as high as 19.19 mg N ·g−1 at 50 °C. Our work has paved the way to the rational design and synthesis of high-performance adsorbents for the removal of nitrogen-containing compounds in real diesel on a large scale. [ABSTRACT FROM AUTHOR]