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In this work, the effective ultra‐deep catalytic adsorptive desulfurization (CADS) using titanium‐silica gel (Ti‐SG) adsorbent at low Ti loading (<1 wt.%) was investigated. The superior CADS capacity (37.3 mg‐S/g‐A) and high TOF value (432 h−1) for dibenzothiophene (DBT) of Ti‐SG adsorbent were achieved at Ti loading of 0.6% with high dispersion and low titanium coordination. The rate equation of catalytic DBT oxidation was described as rDBT=N2kKCHPDBT, where the TiOOR was determined as the intermediate to enable the DBT oxidation to form the corresponding sulfone (DBTO2). The effectiveness of CADS using Ti‐SG adsorbents was verified in real diesels with varied sulfur concentrations and O/S ratios in the dynamic adsorption and multicycle regeneration. This work provides insights on using low‐cost bifunctional catalytic adsorbents at low Ti loadings for effective CADS to realize ultra‐deep desulfurization of transportation fuels. [ABSTRACT FROM AUTHOR]

Adsorbent regeneration is critical for a continuous adsorption-regeneration process and often underestimated. In this work, the regeneration of bifunctional AgXO@SBA-15 for [O]-induced reactive adsorptive desulfurization of liquid fuel is reported and further investigated. The spent AgXO@SBA-15 was regenerated in various types of solvents followed by calcination and tested in multiple desulfurization-regeneration cycles. The effects of regenerate solvents were also compared systematically. The original and regenerated AgXO@SBA-15 was characterized by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, N2 adsorption, X-ray photoelectron spectroscopy and atomic absorption spectrometry. The recovery of desulfurization capacity using various solvents follows the order of acetonitrile > acetone > ethanol > methanol > water. Owing to the complete reduction of silver species to Ag0 and severe agglomeration of Ag0, the bifunctional AgXO@SBA-15 demonstrating > 85% (2.60 mg-S/g) of sulfur removal dramatically reduced to < 46% (1.56 mg-S/g) after only 1st-cycle regeneration. It is suggested that polar organic species strongly adsorbed (or residual) on the spent AgXO@SBA-15, in that case, after solvent wash may contribute to the accelerated decomposition of Ag+ to Ag0 in the following calcination step. The desulfurization capacity decreased rather mildly in the later regeneration runs. Cautious choice of regeneration conditions and strategies to rational design stabilized adsorbents is required to avert the adsorbent deactivation. [ABSTRACT FROM AUTHOR]

With the aid of an azo directing group, Pd-catalyzed C--H bond activation/functionalization of azoarenes (I) with aryl acyl peroxides (II) and (IV) is achieved. The transformation makes it possible to regioselectively introduce acyloxy and aryl groups into azobenzenes by simply changing the reaction temperature and the solvent. [ABSTRACT FROM AUTHOR]