Preparation of ionic liquid supported metal-organic framework Py/MOF-199 and its adsorption desulfurization performance

MOF-199(Cu-BTC) was prepared and the ionic liquid supported MOF-199 adsorbents (Py/MOF-199) were successfully obtained via fixing ionic liquidHnmp H₂PO₄ onto the MOF-199. Adsorbents were characterized via XRD, FT-IR, SEM, and BET methods. The effects of pretreatment conditions of MOF-199, ionic liquid loading method, ionic liquid content, loading temperature and time on adsorptive removal performance of thiophene were studied. The preparation conditions of Py/MOF-199 adsorbent were optimized via orthogonal experiment, and the desulfurization conditions were also optimized. The results show that after the introduction ofHnmp H₂PO₄ the regular octahedron structure of MOF-199 of Py/MOF-199 was maintained unchanged and the average pore diameter was increased. The optimal preparation conditions of Py/MOF-199 adsorbent are pretreating MOF-199 with Soxhlet extraction and drying in vacuum, then loadingHnmp H₂PO₄ using solvothermal method, loading temperature of 50 ℃, loading time of 8 h, ionic liquid content of 7%. The influence of preparation factors on the desulfurization performance of adsorbent is in order:loading temperature > loading time > ionic liquid content. The optimal desulfurization conditions are model oil of 10 mL, Py/MOF-199 dosage of 0.2 g, adsorption under 70 ℃ for 1 h. Under these conditions, the thiophene desulfurization rate over Py/MOF-199 reached 96.7%.