Adsorptive desulfurization through charge-transfer complex using mesoporous adsorbents

Mesoporous supports with a π-acceptor were developed for adsorptive desulfurization of petroleum distillates. Pristine mesoporous Al2O3 and Ti-substituted mesoporous Al2O3 were synthesized and used as supports along with commercial γ-Al2O3 for immobilizing ethylenediamine (EDA) linker followed by the π-acceptor, 2, 7-Dinitro-9-fluorenone (DNF). The adsorbents and supports were characterized using BET, FTIR, TGA techniques to ascertain their physicochemical properties. The extent of π-acceptor functionalization on supports was characterized using XRD, TGA and XPS techniques. Adsorbents were examined for the desulfurization of a model oil feed with 500 ppm of sulfur. The commercial γ-Al2O3-EDA-DNF adsorbent successfully removed 90.4 wt% of sulfur. The substitution of Ti in the framework of mesoporous Al2O3 did not promote its desulfurization efficiency. The higher desulfurization activity of the commercial γ-Al2O3 based adsorbent than that of others is attributed to its textural properties.