Performance of gamma-Al(2)O(3) decorated with potassium salts in the removal of CS(2) from C(5) cracked distillate

Deep desulfurization is a key process for the production of high value-added products from C(5) distillates. In this work, different potassium salt modified gamma-Al(2)O(3) adsorbents were prepared by an incipient-wetness impregnation method and characterized by N(2) adsorption–desorption, SEM-EDS, TEM, CO(2)-TPD, XRD, FT-IR, and IC. The C(5) distillate with a 1200 μg mL(−1) sulfur content is desulfurized to less than 10 μg mL(−1) within 24 hours by the static adsorption method. For the desulfurization in the fix-bed reactor, the breakthrough sulfur capacity of K(2)CO(3)-decorated gamma-Al(2)O(3) reaches 0.76 wt% under the optimized conditions, viz., at 30 °C, with a sulfur content of 50 μg mL(−1) in the raw oil, and a liquid hourly space velocity of 1 h(−1). The desulfurization activity of the exhausted adsorbent can be recovered after regeneration. Selective adsorption of CS(2) includes three processes: adsorption, hydrolysis, and oxidation. CS(2) is first adsorbed on the adsorbent and hydrolyzed to form H(2)S. H(2)S is further oxidized to form S/SO(4)(2−), and then deposits on the surface of the adsorbent. Adsorption, hydrolysis, and oxidation all play essential roles in the removal process of CS(2).