Experimental and Computational Study of Organic Sulfur Removal Proficiency of (Ni, Cu, Co)-Doped ZIF-8 Adsorbents

Abstract

The synthesis and characterization of a series of metal-doped ZIF-8 (metal=Ni, Co and Cu) has been introduced to gain the highly efficient adsorption of dibenzothiophene (DBT) in liquid phase. Under 150 ml DBT/iso-octane, 100–1700 ppm, and 25–85 °C, the excellent efficiency and reusability in DBT removal was achieved and fitted better with the pseudo-first order reaction. The maximum adsorption of 191.84 mg S/g for Ni/ZIF-8 and two steps for intraparticle diffusion study contrary to Cu- and Co-ZIF-8 suggested the presence of Ni-HMeIM clusters in ZIF-8 cavities. Comparing the performance of prepared adsorbents, the order of qmax and PC was the same, i. e. PC Ni/ZIF-8> PC Cu/ZIF-8>PC Co/ZIF-8>PC ZIF-8 and qmax (Ni/ZIF-8)> qmax (Cu/ZIF-8)> qmax (Co/ZIF-8)> qmax (ZIF-8) for both 10% and 100% BT. The prepared adsorbents had the FoMs ranging from 0.05-0.07 that compared to other adsorbents showed the beneficial use for large scale desulfurization process. The endothermic behavior and a homogeneous adsorption was then indicated through thermodynamic and equilibrium studies.