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Frontiers of Chemical Science and Engineering

ISSN 2095-0179

ISSN 2095-0187(Online)

CN 11-5981/TQ

Postal Subscription Code 80-969

2018 Impact Factor: 2.809

Front. Chem. Sci. Eng.    2022, Vol. 16 Issue (9) : 1387-1398    https://doi.org/10.1007/s11705-022-2154-2
RESEARCH ARTICLE
Integrating of metal-organic framework UiO-66-NH2 and cellulose nanofibers mat for high-performance adsorption of dye rose bengal
Yuyao Han1,2, Lei Xia1,2(), Xupin Zhuang1,2, Yuxia Liang3
1. State Key Laboratory of Separation Membranes and Membrane Processes, National Center for International Joint Research on Separation Membranes, Tiangong University, Tianjin 300387, China
2. School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China
3. School of Mathematical Sciences, Tianjin Normal University, Tianjin 300387, China
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Abstract

UiO-66-NH2 is an efficient material for removing pollutants from wastewater due to its high specific surface area, high porosity and water stability. However, recycling them from wastewater is difficult. In this study, the cellulose nanofibers mat deacetylated from cellulose acetate nanofibers were used to combine with UiO-66-NH2 by the method of in-situ growth to remove the toxic dye, rose bengal. Compared to previous work, the prepared composite could not only provide ease of separation of UiO-66-NH2 from the water after adsorption but also demonstrate better adsorption capacity (683 mg∙g‒1 (T = 25 °C, pH = 3)) than that of the simple UiO-66-NH2 (309.6 mg∙g‒1 (T = 25 °C, pH = 3)). Through the analysis of adsorption kinetics and isotherms, the adsorption for rose bengal is mainly suitable for the pseudo-second-order kinetic model and Freundlich model. Furthermore, the relevant research revealed that the main adsorption mechanism of the composite was electrostatic interaction, hydrogen bonding and π–π interaction. Overall, the approach depicts an efficient model for integrating metal-organic frameworks on cellulose nanofibers to improve metal-organic framework recovery performance with potentially broad applications.

Keywords UiO-66-NH2      cellulose nanofibers      rose bengal      adsorption      mechanism     
Corresponding Author(s): Lei Xia   
About author:

Tongcan Cui and Yizhe Hou contributed equally to this work.

Online First Date: 29 April 2022    Issue Date: 20 September 2022
 Cite this article:   
Yuyao Han,Lei Xia,Xupin Zhuang, et al. Integrating of metal-organic framework UiO-66-NH2 and cellulose nanofibers mat for high-performance adsorption of dye rose bengal[J]. Front. Chem. Sci. Eng., 2022, 16(9): 1387-1398.
 URL:  
https://academic.hep.com.cn/fcse/EN/10.1007/s11705-022-2154-2
https://academic.hep.com.cn/fcse/EN/Y2022/V16/I9/1387
Fig.1  (a) The structure of RB; (b) Zr6O4(OH)4 SBU and 2-aminoterephthalic acid.
Fig.2  Fabrication process of CNFM@UiO-66-NH2.
Fig.3  (a) Cellulose acetate nanofibers produced by centrifugal spinning; (b) SEM image of cellulose acetate nanofibers and (c) its diameter distribution; (d) CNFM; (e) SEM image of CNFM and the surface of nanofiber (insert); (f) diameter distribution of cellulose nanofibers; (g) CNFM@UiO-66-NH2; (h) SEM image of CNFM@UiO-66-NH2; (i) EDX elemental mapping of CNFM@UiO-66-NH2.
Fig.4  (a) FTIR spectra of cellulose acetate nanofiber and cellulose nanofiber; (b) FTIR spectra of CNFM, CNFM@UiO-66-NH2, and UiO-66-NH2; (c) XRD patterns of CNFM@UiO-66-NH2 and UiO-66-NH2; (d) the growth trend of UiO-66-NH2 on the CNFM of different weight; (e) TGA analyses of CNFM, CNFM@UiO-66-NH2, and UiO-66-NH2.
Fig.5  (a) N2 adsorption–desorption isotherms of UiO-66-NH2, CNFM@UiO-66-NH2, CNFM@UiO-66-NH2 loaded RB; (b) pore size distribution of CNFM@UiO-66-NH2; (c) the size of RB molecule.
Fig.6  (a) Effect of contact time on RB adsorption of CNFM@UiO-66-NH2 and UiO-66-NH2 (initial concentration = 50 mg?L?1, pH = 3, T = 25 °C); (b) PFO and (c) PSO for the adsorption of RB by CNFM@UiO-66-NH2 and UiO-66-NH2.
Sample C0/(mg?L?1) qe,exp/(mg?g?1) PFO kinetic model PSO kinetic model
qe,cal/(mg?g?1) k1 R2 qe,cal/(mg?g?1) k2 R2
CNFM@UiO-66-NH2 50 244.03 174.95 0.0325 0.968 253.56 0.000741 0.999
UiO-66-NH2 50 145.325 243.67 0.02196 0.983 154.15 0.000528 0.999
Tab.1  Kinetic parameters for RB adsorption by CNFM@UiO-66-NH2 and UiO-66-NH2
Fig.7  Equilibrium isotherms for RB adsorption of (a) CNFM@UiO-66-NH2 and (b) UiO-66-NH2; Langmuir isotherm model of (c) CNFM@UiO-66-NH2 and (d) UiO-66-NH2; Freundlich isotherm model of (e) CNFM@UiO-66-NH2 and (f) UiO-66-NH2.
Sample T/°C Langmuir model Freundlich model
qm/(mg?g?1) KL R2 KF n R2
CNFM@UiO-66-NH2 25 683 0.0079 0.83 8.42 1.175 0.98
35 781.6 0.0067 0.87 7.41 1.125 0.99
45 809.9 0.0065 0.85 7.34 1.116 0.99
UiO-66-NH2 25 309.6 2.581 0.7 2.1 0.918 0.99
35 350.8 2.859 0.93 2.43 0.93 0.99
45 368 3.447 0.63 3.27 0.971 0.99
Tab.2  Langmuir and Freundlich isotherm parameters for RB adsorption by CNFM@UiO-66-NH2 and UiO-66-NH2
Fig.8  (a) Effect of pH on RB adsorption of CNFM@UiO-66-NH2 (initial concentration = 200 mg?L?1, T = 25 °C, contact time = 300 min); (b) Zeta potentials of CNFM@UiO-66-NH2 at varied pH values; (c) XPS spectra of CNFM@UiO-66-NH2 before and after adsorption; (d) TGA and DTG curves of UiO-66-NH2.
Fig.9  XPS high-resolution spectra of (a) Zr 3d, (b) C 1s, (c) N 1s for CNFM@UiO-66-NH2 before and after adsorption.
Fig.10  (a) Adsorption capacities of CNFM@UiO-66-NH2 cycle number in the RB solutions containing other common inorganic salts (T = 25 °C, pH = 7, and the molar concentrations of these salts are consistent with that of RB); (b) the adsorption capacity of CNFM@UiO-66-NH2 after different cycle numbers; (c) the adsorption capacity of CNFM@UiO-66-NH2 and other materials [1,2,3842].
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