Combination of coordinatively unsaturated metal sites and silver nano-particles in a Ni-based metal-organic framework for adsorptive desulfurization

The Ag@CPO-27-Ni composites were deliberately synthesized with different loading amounts of silver nanoparticles in CPO-27-Ni which features unsaturated metal sites and cylindrical one-dimensional channels having a diameter of ca. 11 & Aring; constructed by 2,5-dihydroxybenzene-1,4-dicarboxylate and Ni2+ by a simple one-pot solvothermal method. The well-characterized composites were used as adsorbents to eliminate the aromatic Scompounds of the model oil and fluid catalytic cracking (FCC) oil at room temperature. The experimental results showed that the adsorptive desulfurization followed pseudo-second order reaction kinetics and the adsorptive desulfurization capacity of Ag@CPO-27-Ni (wherein Ag is 1.23 wt%) was notably enhanced as compared with CPO-27-Ni under the same experimental conditions. Impressively, 35 ppmwS dibenzothiophene (DBT) (or benzothiophene (BT))-containing model oil (20 g) was desulfurized to 2.01 +/- 0.27 (or 4.05 +/- 0.26) ppmwS by using 0.2 (or 0.5) g of the composite, respectively; the composite showed much higher selectivity factor of adsorbing DBT to naphthalene than CPO-27-Ni. The notable enhancement in adsorptive desulfurization performance is thought to be due to the interactions between Ag particles and sulfur or pi-system of thiophene moiety in the Scontaining compounds that consequently promote selective attraction between S-containing compounds and the composite. Besides, the composite also showed satisfactory recyclability.

Automated summary

The Ag@CPO-27-Ni composites, synthesized with silver nanoparticles loaded in CPO-27-Ni, showed enhanced adsorptive desulfurization capacity compared to CPO-27-Ni. The interaction between Ag particles and sulfur-containing compounds played a key role in promoting selective attraction and improving desulfurization performance.