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

A Ca-doped Ni/ZnO-Al2O3-SiO2 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), NH3-temperature-programmed desorption (NH3-TPD), N-2 physisorption, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive spectrometry (EDS), are used to evaluate the sorbent. NH3-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.