A novel composite (ZIF-8@PEI-CC) with enhanced adsorption capacity and kinetics of methyl orange

• Published in: Journal of solid state chemistry Vol. 318; p. 123758
• Main Authors: Lei, Yunyun, Liu, Xiaoxun, Zhang, Jilin, Dai, Zi, Zhao, Xiaoya, Liu, Guixia
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.02.2023
• Subjects: Adsorption; Methyl orange; ZIF-8@PEI-CC; Adsorption; Methyl orange; ZIF-8@PEI-CC
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2022.123758

Metal-organic framework materials (MOFs) have shown efficient adsorption performance in organic dye removal. However, its relatively poor capacity and slow adsorption kinetics often limit its further application. Herein, polyethyleneimine (PEI) was cross-linked and encapsulated in ZIF-8 to prepare novel composite (ZIF-8@PEI-CC) by using cyanuric chloride (CC). It was found that the composite exhibited excellent adsorption performance for methyl orange (MO). Compared with ZIF-8 (183 ​mg ​g−1), the adsorption capacity (710 ​mg ​g−1) was significantly enhanced, and it was easier to separate than ZIF-8. Moreover, it shows a faster adsorption rate than ZIF-8. The adsorption kinetics of the ZIF-8@PEI-CC is more consistent with the pseudo-secondary kinetic model. Isotherm of the ZIF-8@PEI-CC is more in line with the Langmuir model. In addition, the ZIF-8@PEI-CC shows high adsorption capacity in a wide pH range (4-11). Therefore, the synthesized composite ZIF-8@PEI-CC has great potential as an effective adsorbent for removing MO. [Display omitted] •The prepared ZIF-8@PEI-CC composites exhibited better adsorption performance on MO dye (710 ​mg ​g−1) than ZIF-8 (183 ​mg ​g−1).•The time for ZIF-8@PEI-CC to reach adsorption equilibrium is three times shorter than ZIF-8.•PEI significantly increased the electrostatic interaction and hydrogen bonds of the composite with MO.•The ZIF-8@PEI-CC composites is easier to be separated than ZIF-8.