Reactive Adsorption Desulfurization of Gasoline over Shaped Ca-Doped NiO/ZnO-Al₂O₃-SiO₂ Adsorbents

A calcium modified NiO/ZnO-Al₂O₃-SiO₂ powder adsorbent was prepared by impregnation-precipitation method and shaped by tablet-pressed method.BET,SEM and XRD characterization results show that the shaped adsorbent has a surface area of 147.51 m²/g,pore volume of 0.28 cm³/g and average pore diameter of 6.38 nm.The crystals of ZnO and NiO were distributed evenly on the shaped adsorbent.Under the conditions of temperature of 420℃,hydrogen pressure of 2.9 MPa,hydrogen to gasoline volume ratio of 52.5 and WHSV of 9.76 h^-1,the shaped adsorbent has a breakthrough sulfur capacity of 46.51 mg/g.Its desulfurization performance was maintained quite well after being regenerated for 5 cycles.It also had a certain denitrification performance.EDS characterization results of the used adsorbents showed a decrease in oxygen content and an increase in sulfur content.The intensity of the characteristic peaks of ZnO in XRD spectrum was weakened,while that of ZnS characteristic peaks increased obviously.A peak was split out on XPS at the binding energy of 852.78 eV,which is the characteristic peak of NiS_x. It means that NiS_x was formed in the reactive adsorption desulfurization process.