Ag2O/MOF-101复合材料的合成及吸附脱硫性能研究  

Synthesis of Ag2O/MOF-101 and Study of Its Adsorption Desulfurization

作　　者：王燕[1] 管旭 石志强 蔡旺锋[1] Wang Yan;Guan Xu;Shi Zhiqiang;Cai Wangfeng(School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学化工学院

出　　处：《天津大学学报（自然科学与工程技术版）》2020年第3期309-316,共8页Journal of Tianjin University：Science and Technology

摘　　要：采用热溶剂法在较低温度下合成了以Cu^2+为中心离子、2-溴对苯二甲酸为配体的金属有机框架材料MOF-101,并通过在其表面负载Ag2O纳米粒子得到Ag2O/MOF-101复合材料.采用XRD、FT-IR、XRF、SEM、N2吸附-脱附测试等表征手段,得到了MOF-101和Ag2O/MOF-101复合材料的组成、结构和形貌特征.通过制得的MOF-101和Ag2O/MOF-101吸附剂在模型油中对噻吩的吸附实验,考察了时间、Ag2O负载量、温度、油剂比对复合材料吸附脱硫能力的影响.通过MOF-101和Ag2O/MOF-101在噻吩-正辛烷模型油中的深度脱硫实验发现,Ag2O的引入增强了吸附剂在低硫浓度的模型油中对痕量含硫化合物的吸附效果.同时,Ag2O/MOF-101复合材料在较低油剂比条件下的吸附容量高于MOF-101.结果显示,吸附温度为30℃、吸附时间为3 h、Ag2O负载量为2.7%时,Ag2O/MOF-101(M)的吸附脱硫能力最佳,将噻吩-正辛烷模型油的硫含量从50×10^-6降低至8.2×10^-6.通过MOF-101和Ag2O/MOF-101复合材料在模型油中对噻吩和甲苯的选择性吸附实验,考察了其对噻吩的吸附容量和选择吸附性能.结果表明,Ag2O/MOF-101复合材料中,基底材料MOF-101为吸附脱硫过程提供活性吸附位点,同时,Ag2O中的Ag+与含硫化合物中S原子之间的相互作用,使Ag2O/MOF-101复合材料对含硫化合物的选择性有显著提升.最后对MOF-101和Ag2O/MOF-101在模型油中对噻吩的吸附过程进行了动力学研究,结果表明,该吸附过程符合准二阶动力学模型,拟合系数在0.990以上.In this study, we successfully synthesized a metal-organic framework, MOF-101, with Cu^2+ as the center and 2-bromine terephthalic acid as ligands by the solvothermal method and then modified the MOF-101 by loading Ag2O nano particles onto its surface. The composition, structure and morphological features of the as-synthesized MOF-101 and Ag2O/MOF-101 were characterized by powder XRD, FT-IR, XRF, SEM, and N2 adsorption-desorption analyses. We investigated the effects of time, Ag2O amounts, temperature, and oil-adsorbent ratio on the adsorption desulfurization of MOF-101 and Ag2O/MOF-101 based on the adsorption of thiophene from model oils. The results of deep desulfurization experiments showed that the introduction of Ag2O enhanced the adsorption of trace sulfur compounds in model oils with a low sulfur concentration. The adsorption capacity of the Ag2O/MOF-101 composite was found to be higher than that of MOF-101 at lower oil-adsorbent ratios. After a 3-h adsorption period at 30 ℃, the sulfur content of the model oil had reduced from 50×10^-6 to 8.2×10^-6 by the presence of Ag2O/MOF-101(M) in which the Ag2O content was 2.7%. The introduction of Ag2O significantly increased the selective adsorption of thiophene versus toluene. We inferred that the base material MOF-101 provided active sites for adsorption, and that there had been atomic interactions between Ag^+ and S in thiophene, which significantly improved the selective adsorption of Ag2O/MOF-101 for the sulfur compound. Finally, we studied the kinetics of thiophene adsorption onto MOF-101 and Ag2O/MOF-101. The results showed that the adsorption process followed a quasi-second-order kinetics model and the fitting coefficient was higher than 0.990.

关 键 词：金属有机框架 吸附脱硫 噻吩 选择吸附 

分 类 号：U214.7[交通运输工程—道路与铁道工程]