Reactive Adsorption Desulfurization of Fluidized Catalytically Cracked (FCC) Gasoline over a Ca-Doped Ni-ZnO/Al₂O₃–SiO₂ Adsorbent

Abstract

A Ca-doped Ni/ZnO−Al 2 O 3 −SiO 2 adsorbent was prepared for reactive adsorption desulfurization (RADS) of fluidized catalytically cracked (FCC) gasoline. Various characterizations, such as H 2 −temperature-programmed reduction (H 2 -TPR), the H 2 /O 2 pulse titration (HOPT), NH 3 −temperature-programmed desorption (NH 3 -TPD), N 2 physisorption, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive spectrometry (EDS), are used to evaluate the sorbent. NH 3 -TPD results showed that Ca loading could reduce the mild and strong acidities of the sorbent surface. HOPT results indicated that Ca doping could promote the dispersity and specific surface area of the nickel component. The adsorbent doped with 1 wt % Ca obtained a higher efficiency of desulfurization and regeneration performance than the undoped one. The breakthrough sulfur capacities of the fresh and the regenerated Ca-doped adsorbents could reach 54.07 mg/g and 46.23 mg/g, respectively, at a breakthrough sulfur level of 10 ppmw with a loss of 0.23 gasoline octane number. The introduction of Ca contributes to the reduction of surface acidity of adsorbent and also reduces the carbon deposition in the process of RADS, improving the desulfurization ability and the regeneration performance of the adsorbent.

The Role of NiO in Reactive Adsorption Desulfurization Over NiO/ZnO-Al2O3-SiO2 Adsorbent

“…As H 2 can considerably improve the effect of desulfurization, desulfurization performance in H 2 is much better than that in N 2 . The presence of hydrogen obviously reduces the formation of surface carbon deposits during the desulfurization process [22][23][24]. Figure 2 shows the XRD patterns of used adsorbents under different RADS conditions.…”

“…The desulfurization experiments were carried out in a continuous micro fixed-bed reactor [22][23][24]. A total of 3 g of adsorbent in the oxidized form was loaded into the reactor per run.…”

Reactive adsorption desulfurization of NiO and Ni0 over NiO/ZnO–Al2O3–SiO2 adsorbents: role of hydrogen pretreatment

“…The desulfurization experiments were conducted in a continuous micro xed-bed reactor. 23,24 A total of 3 grams of adsorbent in the oxidized form was loaded into the reactor per run. Before the reaction, the oxidized form sorbent was reduced by hydrogen at a ow rate of 140 mL min À1 under 2.0 MPa and 440 C for 2 h. Then the FCC gasoline was pumped into the reactor.…”

“…In our previous works the effects of dispersion of Ni species and acidity of adsorbent surface on the desulfurization of NiO/ZnO-Al 2 O 3 -SiO 2 sorbents were discussed. 23,24 It was noticed that hydrogen pre-treatment had little effect on desulfurization. In this work, reduced and unreduced NiO/ZnO-Al 2 O 3 -SiO 2 adsorbents have been prepared to verify whether hydrogen pretreatment contributes to the desulfurization process.…”

Difunctional Adsorbents Ni/ZnO–HZSM-5 on Adsorption Desulfurization and Aromatization of Olefin Reaction

“…Skrzypski et al [14] used Mo as auxiliaries to prepare adsorbents which could increase the specific surface area and pore volume. Ju et al [15] used Ca to promote the dispersion of active Ni sites and enhance desulfurization and regeneration ability of adsorbents.…”