Selective Dye Adsorption by Zeolitic Imidazolate Framework-8 Loaded UiO-66-NH2
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Synthesis of UiO-66-NH2
2.3. Synthesis of ZIF-8-Loaded UiO-66-NH2
2.4. Characterization
2.5. Adsorption Experiments of Dyes
3. Results and Discussion
3.1. Adsorbents Characterizations
3.2. Separation Selectivity in the Mixed Dye Solution
3.3. Adsorption Isotherms
3.4. Kinetic Studies
3.5. Effect of pH on Adsorption
3.6. Adsorption Thermodynamics
3.7. Reusability of ZIF-8-Loaded UiO-66-NH2
3.8. Adsorption Mechanism
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample | SBET (m2/g) | Smicro (m2/g) | Vmicro (cm3/g) | Pore Width (nm) |
---|---|---|---|---|
ZIF-8 | 1938.859 | 1841.897 | 0.646 | 0.524 |
UiO-66-NH2 | 897.779 | 801.012 | 0.308 | 1.232 |
1-ZIF-8@UiO-66-NH2 | 651.895 | 596.664 | 0.233 | 0.548 |
Adsorbent | Langmuir Isotherm | Freundlich Isotherm | ||||||
---|---|---|---|---|---|---|---|---|
qmax | KL | RL | R2 | KF | 1/n | n | R2 | |
1-ZIF@UiO | 173.01 | 1 | 0.0175 | 0.999 | 83.89 | 0.2297 | 4.35 | 0.937 |
UiO-66-NH2 | 55.04 | 0.79 | 0.0324 | 0.999 | 34.50 | 0.1297 | 7.71 | 0.972 |
Adsorbents | qmax (mg/g) | References |
---|---|---|
UiO-66 | 69.8 | [33] |
UiO-66 | 90 | [34] |
UiO-66-NH2 | 90.88 | [35] |
Acid- promoted UiO-66 | 13.0 | [29] |
UiO-66-P composite | 91.1 | [36] |
Ce(III)-doped UiO-66 | 145.1 | [37] |
UiO-66-NH2 | 55 | Our work |
ZIF-8-loaded UiO-66-NH2 | 173 | Our work |
Adsorbent | C0 | qe | Pseudo-First-Order Kinetic | Pseudo-Second-Order Kinetic | |||||
---|---|---|---|---|---|---|---|---|---|
qe | K1 | R2 | qe | K2 | R2 | Rate | |||
1-ZIF@UiO | 10 | 90 | 33.64 | 0.0066 | 0.727 | 92.25 | 0.00050 | 0.999 | 0.046 |
20 | 132 | 50.68 | 0.0099 | 0.897 | 135.32 | 0.00039 | 0.999 | 0.053 | |
30 | 160 | 62.90 | 0.0076 | 0.866 | 164.47 | 0.00030 | 0.999 | 0.049 | |
UiO-66-NH2 | 5 | 36 | 21.48 | 0.0053 | 0.984 | 36.44 | 0.00068 | 0.995 | 0.025 |
10 | 43 | 21.03 | 0.0079 | 0.937 | 44.74 | 0.00083 | 0.999 | 0.037 | |
20 | 50 | 39.23 | 0.0129 | 0.941 | 53.22 | 0.00062 | 0.999 | 0.033 |
Adsorbent | C (mg/L) | Intra-Particle Diffusion Kinetic Model | |||||
---|---|---|---|---|---|---|---|
K1 | C1 | R2 | K2 | C2 | R2 | ||
1-ZIF@UiO | 10 | 8.27 | 1.16 | 0.983 | 0.47 | 77.48 | 0.913 |
20 | 12.91 | 2.54 | 0.959 | 0.79 | 112.42 | 0.961 | |
30 | 14.17 | 11.27 | 0.972 | 1.28 | 130.13 | 0.950 | |
UiO-66-NH2 | 5 | 1.53 | 7.97 | 0.985 | 0.34 | 26.40 | 0.982 |
10 | 2.52 | 8.29 | 0.981 | 0.26 | 36.58 | 0.995 | |
20 | 2.81 | 10.48 | 0.982 | 0.26 | 44.31 | 0.964 |
Adsorbent | CONCENTRATION (mg/L) | ΔH° (kJ/mol) | ΔS° (J/mol K) | ΔG° (kJ/mol) | |||
---|---|---|---|---|---|---|---|
298 K | 308 K | 318 K | R2 | ||||
1−ZIF@UiO | 10 | −18.46 | −27.89 | −10.15 | −9.87 | −9.59 | 0.977 |
20 | −9.83 | −7.18 | −7.69 | −7.62 | −7.55 | 0.970 | |
30 | −9.11 | −10.29 | −6.05 | −5.95 | −5.84 | 0.996 | |
UiO−66−NH2 | 5 | −21.31 | −44.93 | −7.92 | −7.47 | −7.02 | 0.850 |
10 | −20.11 | −50.84 | −4.96 | −4.46 | −3.95 | 0.936 | |
20 | −21.29 | −60.86 | −3.15 | −2.54 | −1.93 | 0.963 |
Adsorbate | Molecular Structure | Size (nm) |
---|---|---|
Methylene blue (MB+) | 1.38 × 0.64 | |
Methyl orange (MO−) | 1.54 × 0.48 | |
Rhodamine B (RhB+) | 1.41 × 0.98 |
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Zhang, H.; Shi, X.; Li, J.; Kumar, P.; Liu, B. Selective Dye Adsorption by Zeolitic Imidazolate Framework-8 Loaded UiO-66-NH2. Nanomaterials 2019, 9, 1283. https://doi.org/10.3390/nano9091283
Zhang H, Shi X, Li J, Kumar P, Liu B. Selective Dye Adsorption by Zeolitic Imidazolate Framework-8 Loaded UiO-66-NH2. Nanomaterials. 2019; 9(9):1283. https://doi.org/10.3390/nano9091283
Chicago/Turabian StyleZhang, Hao, Xiaobo Shi, Jialiang Li, Parveen Kumar, and Bo Liu. 2019. "Selective Dye Adsorption by Zeolitic Imidazolate Framework-8 Loaded UiO-66-NH2" Nanomaterials 9, no. 9: 1283. https://doi.org/10.3390/nano9091283