学术论文

      金属有机骨架材料MIL-101吸附脱硫性能的研究

      Adsorptive Performance of Sulfur Compounds on Metal Organic Framework Material MIL-101

      摘要:
      采用水热合成法制备了金属有机骨架材料MIL-101,基于固定床动态吸附实验,研究了室温下MIL-101对模型气体中的甲硫醚、乙硫醇及硫化氢的吸附性能和脱除机理.对硫化后的样品进行XRD和TG-MS分析,并用密度泛函理论进行MIL-101吸附硫化物的计算.研究结果表明,MIL-101对甲硫醚有最佳的吸附容量(m(S)/m(MOFs)=24.2 mg/g),其次为乙硫醇(m(S)/m(MOFs)=14.9 mg/g),硫化氢最差(m(S)/m(MOFs)=5.8 mg/g).3种硫化物在MOFs上吸附后并未破坏骨架主体结构;吸附后甲硫醚主要以分子形态存在于MOFs骨架中,硫化氢则与骨架发生化学作用.理论计算表明,MIL-101对硫化物的吸附主要发生在不饱和金属中心上,且硫化物的平均吸附能随着被吸附分子数量的增加而减弱.不饱和金属位对硫化物吸附的强弱顺序为甲硫醚,乙硫醇,硫化氢,这与实验得到的3种硫化物的硫容顺序相一致.
      Abstract:
      MIL-101 was synthesized by hydrothermal method.The fixed bed was employed to carry out the dynamic adsorption experiments for dimethyl sulfide,ethyl mercaptan and hydrogen sulfide at ambient temperature.The sulfuretted samples were characterized by XRD and TG-MS techniques.The density functional theory was used to calculate the adsorption energies of three sulfides over the MIL-101.It was found that the adsorption capacity is m(S)/m(MOFs)=24.2 mg/g,m(S)/m(MOFs)=14.9 mg/g and m(S)/m(MOFs)=5.8 mg/g for dimethyl sulfide,eth-yl mercaptan and hydrogen sulfide,respectively.The framework of MIL-101 was not damaged after breakthrough experiments.Results show that dimethyl sulfide was adsorbed on the MIL-101 in its molecular form,whereas hydrogen sulfide could react with MIL-101.The theoretical calculation demonstrated that coordinatively unsaturated metal site (CUS) is the main position to adsorb sulfide,and the average adsorption energies over CUS of MIL-101 weaken with the in-creased number of sulfide.The adsorption sequence over CUS is CH3SCH3 ,CH3CH2SH,H2S, which is coincidence with the order of sulfur capacity obtained from experiment results.
      作者: 陈志平 [1] 张振荣 [2] 凌丽霞 [3] 王宝俊 [1] 上官炬 [1] 樊惠玲 [1]
      Author: CHEN Zhiping [1] ZHANG Zhenrong [2] LING Lixia [3] WANG Baojun [1] SHANGGUAN Ju [1] FAN Huiling [1]
      作者单位: 太原理工大学煤科学与技术省部共建国家重点实验室培育基地,太原,030024 山西省应用化学研究所,太原,030027 太原理工大学化学化工学院,太原,030024
      刊 名: 太原理工大学学报 ISTICPKU
      年,卷(期): 2017, 48(5)
      分类号: TQ424.3 TQ426.61
      在线出版日期: 2017年10月27日
      基金项目: 国家自然科学基金资助项目:三维有序大孔复合金属氧化物脱硫剂的构建及水对脱硫作用行为研究,国家自然科学青年基金资助项目:热解和气化煤气中H2S和Hg同时脱除的理论研究,山西省国际科技合作资助项目:新型多孔氧化锌常温深度脱硫净化