Adsorption desulfurization of model gasoline by metal–organic framework Ni3(BTC)2

This work presented the synthesis of Ni-based metal-organic framework material with a paddle-wheel structure Ni 3 (BTC) 2 (Ni-BTC) and its application in thiophene (TP) adsorption from gasoline distillate by batch method. Adsorption isotherms of TP, cyclohexene , and toluene in cyclohexane onto Ni-BTC were conducted at 298–308 K to interpret the different effect of cyclohexene and toluene on TP adsorption. The results showed that, compared with cyclohexene, toluene addition in model gasoline led to a more evident decline in sulfur capacity of Ni-BTC, which is opposite to isostructural HKUST-1. The adsorption isotherms of TP, cyclohexene and toluene fit Langmuir model, S-type model and Temkin model well, respectively, indicating that the adsorption mechanisms of TP and the two competitors are different from one another. The adsorption capacities on Ni-BTC followed the order of cyclohexene < toluene < TP at the same equilibrium concentrations , implying the order of the adsorption affinities, which is in good agreement with the different extent of influence by the two competitors. The enthalpy of TP adsorption on Ni-BTC was estimated to be −80.01 kJ/mol, almost twice that on HKUST-1. The poor reusability of Ni-BTC in batch experiment, which is owing to its sensitivity to the air, can be prevented from regenerating used Ni-BTC in fixed-bed reactor by N 2 flow. The difference between Ni-BTC and HKUST-1 in maximum adsorption capacity ( q 0 ), Δ H of TP adsorption, and stability demonstrates that the central metal in isostructural MOFs plays a key role in adjusting the desulfurization performance, which may open up a potential avenue for the development of MOF-based adsorbents with superior desulfurization performance.