Thiophene capture with complex adsorbent SBA-15/Cu(I)

To develop a more robust desulfur adsorbent to be used for removing thiophenes from fuel oils, a complex adsorbent, SBA-15/Cu(I), was prepared using SBA-15 as the substrate of CuCl. The two-dimensional ordered structure remained in such adsorbent as was proven by examinations with XRD, SEM, and TEM analyses and N-2 adsorption at 77 K. Three simulated oils were prepared to represent different types of oil with respect to the content of aromatic components: ALO, the aliphatic oil, was simulated by n-octane; ARO, the aromatic oil, was simulated by benzene; LRO, aliphatic and aromatic oil mixture, was simulated by a mixture composed of 80 wt % n-octane and 20 wt % benzene. Thiophene was used to represent the sulfur component of oils. The desulfur performance of the prepared adsorbent was tested with the simulated oils at room temperature in terms of breakthrough curves, from which the breakthrough capacity and the saturation capacity of the adsorbent for sulfur element were determined. Other adsorbents including Y-type zeolite, 13 X zeolite, active carbon, and active alumina were also used as the substrate of CuCl, and the desulfur performance of these adsorbents were compared with SBA-15/Cu(I). It was shown that SBA-15/Cu(I) possesses the highest sulfur capacity, even higher than that reported previously in the literature. In addition, it shows stronger durability in the presence of aromatic components and moisture. The saturated adsorbents can be regenerated with nitrogen sweeping at 623 K for 2 h and heated at 723 K for 2 h in a helium atmosphere. About 90% of the desulfur capacity was recovered after regeneration.