离子液体负载的金属框架Py/MOF-199的制备及其吸附脱硫性能

制备了金属框架MOF-199(Cu-BTC),并将[Hnmp][H2PO4]离子液体负载到MOF-199上合成了离子液体负载的金属框架Py/MOF-199。对吸附剂进行了X射线衍射、红外光谱、扫描电镜、比表面积表征。考察了MOF-199预处理条件、离子液体负载方式、负载量、负载温度、负载时间对噻吩吸附脱除性能的影响,通过正交实验优化了吸附剂的制备条件和吸附脱硫条件。结果表明,离子液体改性得到的Py/MOF-199保持了MOF-199的规则的八面体结构。Py/MOF-199的适宜制备条件为:采用二氯甲烷索氏提取并真空干燥法进行预处理MOF-199后,再用溶剂热法负载[Hnmp][H_2PO_4],负载温度为50℃,负载时间为8 h,负载量为7%。各因素对吸附剂脱硫性能影响大小顺序为:负载温度负载时间离子液体负载量。适宜Py/M OF-199吸附脱硫条件为:模拟油为10 mL,吸附剂用量0.2 g,吸附温度70℃,吸附时间1 h。在此条件下,噻吩脱除率可达到96.7%。

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 liquid[Hnmp] [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 of[Hnmp] [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 loading[Hnmp] [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%.