Enhanced adsorption of dibenzothiophene with zinc/copper-based metal-organic frameworks

A novel type of bimetallic-organic porous material (Zn/Cu-BTC) has been successfully synthesized with Zn2+ replacing Cu2+ in the paddle wheel unit. The as-synthesized sorbents were characterized by XRD, SEM, ICP, and TGA analyses and N-2 adsorption at 77 K. The desulfurization performance of the prepared adsorbents was evaluated by the selective adsorption of dibenzothiophene (DBT) from simulated oils in a fixed-bed breakthrough column at room temperature (298 K). From the obtained breakthrough curves, both the breakthrough capacity and the saturation capacity of the adsorbents for the sulfur element were determined. The results showed that Zn/Cu-BTC exhibited high desulfurization capacities, which are even superior to those reported previously in the literature. In addition, these novel adsorbents possessed good durability and affinities for the adsorption of dibenzothiophene in the presence of aromatic components and moisture. The saturated adsorbent Zn/Cu-BTC can be regenerated with a nitrogen atmosphere sweeping at 573 K for 5 h. More than 90% of the desulfurization capacity was recovered after regeneration.