Effect of Doping Al on the Desulfurization Performance of Ag/SiO₂–Al₂O₃ Aerogel Composite Adsorbents

Abstract

Ag/SiO 2 −Al 2 O 3 aerogel composites with different molar ratio of Si to Al were prepared by the sol−gel synthesis followed by drying under atmospheric pressure and then characterized by XRD, FT-IR, BET, SEM, XRF, TG-DTG, and Py-FTIR, respectively. The effect of doping Al on their physicochemical properties and adsorption desulfurization performance was investigated in comparison with Ag/ SiO 2 . The incorporation of Al in Ag/SiO 2 resulted in a gradual decrease in the specific surface area, an increase in the actual content of Ag, and an appearance of Bronsted acid centers. The actual content of Ag in Ag/SiO 2 −Al 2 O 3 -n increased first and then decreased with the increase in Al content. Doping Al in Ag/SiO 2 led to an improvement in the adsorption capacity and the adsorptive selectivity for thiophene at the presence of toluene and cyclohexene, as well as the solvent washing regeneration performance, attributed to the adsorption of thiophenics on Ag/SiO 2 −Al 2 O 3 -n by π-complexation of Ag(I) and the acid−base interaction of Lewis and Bronsted centers with thiophenics simultaneously, and the increase in the actual content of Ag in the adsorbents. Ag/SiO 2 −Al 2 O 3 -100 had the largest adsorption capacity for thiophene and benzothiophene, 12.2 mg of S/g ads (0.57 mmol of S/mmol of (Ag + Al)) and 17.7 mg of S/g ads (0.53 mmol of S/mmol of (Ag + Al)), respectively.

Enhanced Adsorption Desulfurization Performance over CuCeY Zeolites Prepared by Low‐Temperature Calcination under H2 Atmosphere

“…It′s worth mentioning that the weak B acid centers from hydroxyl groups located in the supercages increase with the increase of Cu ion content (see Figure 13 and 14). These hydroxyl groups may be an important factor of the increase of sulfur adsorption selectivity of CuCeY zeolites for TAMO [11,39,82] . It needs to be further studied in detail by co‐adoption of sulfur compounds and aromatics or and olefins over CuCeY zeolites by using FTIR as before [78]…”

“…These hydroxyl groups may be an important factor of the increase of sulfur adsorption selectivity of CuCeY zeolites for TAMO. [11,39,82] It needs to be further studied in detail by coadoption of sulfur compounds and aromatics or and olefins over CuCeY zeolites by using FTIR as before. [78]…”

“…According to the difference of the interaction modes between the thiophenic sulfur compounds and the metal ions in materials, metal ions modified porous materials can be divided into π-complexation adsorbents and direct sulfur-metal interaction (SÀ M) adsorbents, as shown in Figure 1. [7][8][9][10][11][12][13] The transition metal ions modified porous materials belong to the former, while rare earth metal ions modified porous materials belong to the latter. The π-complexation adsorbents have high adsorptive capacities of thiophenic sulfur compounds, but their adsorptive capacities decrease rapidly when the thiophenic sulfur compounds and aromatics coexist in the fuel.…”

“…These materials include activated carbons, metal‐organic frameworks (MOFs), mesoporous silicas, metal oxides and zeolites. According to the difference of the interaction modes between the thiophenic sulfur compounds and the metal ions in materials, metal ions modified porous materials can be divided into π‐complexation adsorbents and direct sulfur‐metal interaction (S−M) adsorbents, as shown in Figure 1 [7–13] . The transition metal ions modified porous materials belong to the former, while rare earth metal ions modified porous materials belong to the latter.…”

High‐performance adsorptive desulfurization by ternary hybrid boron carbon nitride aerogel

“…In recent years, aerogel with a three‐dimensional interconnected porous network, assembled by coherent nanoparticles or polymer molecules, 34 has been receiving considerable attention because of its high surface area and flexible porous structure, which endow this kind of material with abundant active sites and high adsorption rate for a variety of adsorption applications. SiO 2 aerogel with a uniform pore structure is the widely investigated material for adsorptive desulfurization in the past few years 35‐39 . However, it shows weak surface interactions with aromatic sulfur compounds, which greatly restrict its ADS performance.…”