Shi Jiaqi, Han Rui, Lu Shuangchun, Liu Qingling
Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Technology, Tianjin University, Tianjin 300350, China; State Key Laboratory of Engines, Tianjin University, Tianjin 300350, China.
Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Technology, Tianjin University, Tianjin 300350, China; State Key Laboratory of Engines, Tianjin University, Tianjin 300350, China.
J Environ Sci (China). 2021 Sep;107:111-123. doi: 10.1016/j.jes.2021.01.030. Epub 2021 Feb 13.
A series of highly-hydrophobic MIL-53-Al (MIL = Materials of Institut Lavoisier) frameworks synthesized via decoration of the Al-OH groups by alkyl phosphonic acid were developed as adsorbents for removing acetone from humid gas streams. The newly prepared materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), N adsorption-desorption and thermogravimetric analysis (TGA). Their adsorption behaviors toward acetone vapor under dry and wet conditions were studied subsequently. Results showed that alkyl phosphonic acid was successfully grafted into MIL-53-Al skeleton through coordinating interaction with Al generating MIL-53-Al@C (x = 12, 14, 18). The MIL-53-Al@C exhibited similar crystal structure and thermal stability to parent MIL-53-Al. Furthermore, the modified materials showed significantly enhanced hydrophobicity. The water vapor uptake of MIL-53-Al@C decreased by 72.55% at 75% relative humidity (RH). Dynamic adsorption experiments demonstrated that water vapor had almost no effect on the acetone adsorption performance of MIL-53-Al@C. Under the condition of 90% RH, the acetone adsorption capacity of MIL-53-Al@C was 102.98% higher than that of MIL-53-Al. Notably, MIL-53-Al@C presented excellent adsorption reversibility and regeneration performance in 10 adsorption-desorption cycles. Taken together, the strategy of metal-OH group modification is an attractive way to improve the acetone adsorption performance over metal-organic frameworks (MOFs) under humid conditions. Besides, MIL-53-Al@C would be deemed as a promising candidate for capturing acetone in high moisture environment.
通过用烷基膦酸修饰Al-OH基团合成了一系列高疏水性的MIL-53-Al（MIL = 拉瓦锡研究所材料）骨架，并将其开发为从潮湿气流中去除丙酮的吸附剂。通过X射线衍射（XRD）、傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）、N吸附-脱附和热重分析（TGA）对新制备的材料进行了表征。随后研究了它们在干燥和潮湿条件下对丙酮蒸气的吸附行为。结果表明，烷基膦酸通过与Al的配位相互作用成功接枝到MIL-53-Al骨架中，生成MIL-53-Al@C（x = 12、14、18）。MIL-53-Al@C表现出与母体MIL-53-Al相似的晶体结构和热稳定性。此外，改性材料的疏水性显著增强。在75%相对湿度（RH）下，MIL-53-Al@C的水蒸气吸附量降低了72.55%。动态吸附实验表明，水蒸气对MIL-53-Al@C的丙酮吸附性能几乎没有影响。在90%RH条件下，MIL-53-Al@C的丙酮吸附容量比MIL-53-Al高102.98%。值得注意的是，MIL-53-Al@C在10次吸附-脱附循环中表现出优异的吸附可逆性和再生性能。综上所述，金属-OH基团改性策略是在潮湿条件下提高金属有机骨架（MOF）对丙酮吸附性能的一种有吸引力的方法。此外，MIL-53-Al@C将被视为在高湿度环境中捕获丙酮的有前途的候选材料。
