Cu(I)-faujasite-type zeolites with hierarchical structure for adsorption desulfurization

Faujasite (FAU)-type zeolites are promising adsorbents for the removal of sulfides from fuels, but their micropores are not capable to accommodate the large-sized thiophenic compounds. FAU zeolites (NaX and NaY with the low and high Si:Al ratios, respectively) with hierarchical micro/mesoporous structures were synthesized by sequential acid-base treatment to enhance the adsorption capacity and reduce the limitations of diffusion for the sulfides. To further to improve the desulfurization performance, the hierarchical structure of FAU zeolites containing Cu+ were prepared by ion-exchange and methanol vapor-induced reduction methods at a relatively low temperature (473 K). For the large-sized benzothiophene, both the HP-Cu(I)Y and HP-Cu(I)X zeolites with mesopores have a very high adsorption capacity, reaching 51.8 mg S/g and 56.1 mg S/g, respectively. In addition, the results show that HP-Cu(I)X has a higher adsorption capacity than that of some other FAU-type adsorbents reported.