Synthesis of reusable NH2-MIL-125(Ti)@polymer monolith as efficient adsorbents for dyes wastewater remediation

作者：Peng Yao, Yang Liu, Tang Xue, Shuxiang Lü, Zhen Li, Yue Yao · 发表于：Green Chemical Engineering · 年份：2022 · DOI：10.1016/j.gce.2022.06.004 · 被引用次数：32 · 研究领域：Metal-Organic Frameworks: Synthesis and Applications、Adsorption and biosorption for pollutant removal、Magnesium Oxide Properties and Applications

NH2-MIL-125(Ti) is a Ti-MOFs with high adsorption properties and is therefore widely used for wastewater purification. However, the powdered MOF material suffers from the disadvantages of being difficult to separate and being potentially wasted due to easy agglomeration, which limits its application in practical applications. Here, a mesoporous Ti-MOF/polymer (PEG, PVA, and PAM) monolithic material was prepared by freeze casting in liquid nitrogen (−196 °C) as an adsorbent for wastewater remediation. The composites could be easily picked up with tweezers and used for recovery tests. Characterization results such as XRD, BET, FT-IR, and SEM proved the successful synthesis of Ti-MOF/polymer. Adsorption tests using 100 mg/L methylene blue (MB) simulated wastewater showed that the Ti-MOF/PEG monolithic material had the best adsorption capacity. The order of adsorption was [email protected] (747.4 mg/g) > [email protected] (687.4 mg/g) > [email protected] (633.7 mg/g) > Ti-MOF (571.4 mg/g). The effects of polymer dosage, different pollutants (methylene blue, methyl orange, indigo, actual textile wastewater), pH, anions, and cations on the adsorption effect of Ti-MOF/polymer were also investigated. It was demonstrated that all the above pollutants were well adsorbed by this Ti-MOF/polymer in the pH range 3–9. The adsorption isotherms and kinetic data are fully consistent with the Langmuir and pseudo-secondary models. This suggests that the adsorption between the pollutant and the a...