A metal-OH group modification strategy to prepare highly-hydrophobic MIL-53-Al for efficient acetone capture under humid conditions  

作　　者：Jiaqi Shi Rui Han Shuangchun Lu Qingling Liu 

机构地区：[1]Tianjin Key Lab of Indoor Air Environmental Quality Control,School of Environmental Science and Technology,Tianjin University,Tianjin 300350,China [2]State Key Laboratory of Engines,Tianjin University,Tianjin 300350,China

出　　处：《Journal of Environmental Sciences》2021年第9期111-123,共13页环境科学学报（英文版）

基　　金：supported by the National Key R&D Program of China(Nos.2016YFC0205300,2019YFC1904100 and 2019YFC1904102);the National Engineering Laboratory for Mobile Source Emission Control Technology of China(No.NELMS2017A03);the Natural National Science Foundation of China(Nos.21503144 and 21690083);the Tianjin Research Program of Ecological Environmental Treatment(Nos.18ZXSZSF00210 and 18ZXSZSF00060);the Tianjin Research Program of Application Foundation and Advanced Technique(No.16JCQNJC05400)。

摘　　要：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(FTIR), scanning electron microscope(SEM), N_(2) 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 Al3+generating MIL-53-Al@C_(x)(x = 12, 14, 18).The MIL-53-Al@C_(x) 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_(14) 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_(14).Under the condition of 90% RH, the acetone adsorption capacity of MIL-53-Al@C_(14) was 102.98% higher than that of MIL-53-Al.Notably, MIL-53-Al@C_(14) 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_(14) would be deemed as a promising candidate for capturing acetone in high moisture environment.

关 键 词：HYDROPHOBIZATION Alkyl phosphonic acid Al-OH groups Adsorption Moisture 

分 类 号：TQ424[化学工程] X701[环境科学与工程—环境工程]