Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jan 10;10(1):131.
doi: 10.3390/nano10010131.

Design of Crosslinked Hydrogels Comprising Poly(Vinylphosphonic Acid) and Bis[2-(Methacryloyloxy)Ethyl] Phosphate as an Efficient Adsorbent for Wastewater Dye Removal

Ismail Anil  1 , Seyda Tugba Gunday  2 , Ayhan Bozkurt  2 , Omar Alagha  1
Affiliations

Design of Crosslinked Hydrogels Comprising Poly(Vinylphosphonic Acid) and Bis[2-(Methacryloyloxy)Ethyl] Phosphate as an Efficient Adsorbent for Wastewater Dye Removal

Ismail Anil et al. Nanomaterials (Basel). .

Abstract

The development of adsorbents with high adsorption capacity and fast separation is of utmost importance for the environmental management of dye-bearing wastewaters. Within this scope, crosslinked hydrogels including poly(vinylphosphonic acid) (PVPA) and bis[2-(methacryloyloxy)ethyl] phosphate (BMEP) were designed with varying mole ratios of BMEP (5-40%). The Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) results revealed that the fabrication of crosslinked PVPA-BMEP hydrogels enhanced: (i) functionalities of PA groups in the structure of hydrogels, (ii) thermal stabilities up to 250 °C, and (iii) interaction between methylene blue (MB) molecules and hydrogels. The pseudo second-order kinetic model best described the experimental adsorption data. The behaviors of the isotherms were more appropriate for Langmuir than Freundlich isotherm for the experimental data. PVPA-BMEP (40%) hydrogel indicated a fast and an outstanding MB adsorption capacity of 2841 mg g-1, which has not been reported yet for polymer hydrogels, to the best of our knowledge. The thermodynamic studies concluded that MB adsorption process was spontaneous and exothermic in nature. The overall results suggest that the designed and fabricated PVPA-BMEP hydrogels have great potential for the efficient removal of coloring materials from wastewaters.

Keywords: adsorption isotherm; adsorption kinetic; methylene blue adsorption; poly(vinylphosphonic acid); wastewater dye removal.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Schematic illustration for the synthesis of poly(vinylphosphonic acid)-bis[2-(methacryloyloxy)ethyl] phosphate (PVPA-BMEP) hydrogels.
Figure 2
Figure 2
(a) Fourier transform infrared (FT-IR) spectra of methylene blue (MB) and PVPA-BMEP hydrogels with 5 and 40% of BMEP fractions before and after MB adsorption, (b) thermogravimetric (TG) spectra of PVPA-BMEP hydrogels.
Figure 3
Figure 3
Scanning electron microscope (SEM) images of hydrogels: (a): PVPA-BMEP (5%), (b): PVPA-BMEP (5%) after MB adsorption, (c): PVPA-BMEP (40%), and (d): PVPA-BMEP (40%) after MB adsorption. Red arrows: MB molecules.
Figure 4
Figure 4
Transmission electron microscope (TEM) images of hydrogels (scale bar = 500 nm): (a): PVPA-BMEP (5%) and (b): PVPA-BMEP (40%).
Figure 5
Figure 5
Effect of initial solution pH (a) and adsorbent dosage (b) on MB adsorption.
Figure 6
Figure 6
Effect of contact time (a–c) and initial MB concentration (d) on MB adsorption.
Figure 7
Figure 7
The linear fits of kinetic models to the experimental data at C0 = 100 mg L−1; (a): pseudo first-order (PFO), (b): pseudo second-order (PSO), (c): intraparticle diffusion (IPD), and (d): Elovich model.
Figure 8
Figure 8
The adsorption isotherms of MB on (a): PVPA-BMEP (5%), (b): PVPA-BMEP (10%), (c): PVPA-BMEP (20%), and (d): PVPA-BMEP (40%).
Figure 9
Figure 9
Linear plots of ln(KD) vs. 1/T for adsorption of MB on PVPA-BMEP hydrogels.
See this image and copyright information in PMC

References

    1. Rafatullah M., Sulaiman O., Hashim R., Ahmad A. Adsorption of methylene blue on low-cost adsorbents: A review. J. Hazard. Mater. 2010;177:70–80. doi: 10.1016/j.jhazmat.2009.12.047. - DOI - PubMed
    1. Zargar B., Parham H., Rezazade M. Fast removal and recovery of methylene blue by activated carbon modified with magnetic iron oxide nanoparticles. J. Chin. Chem. Soc. 2011;58:694–699. doi: 10.1002/jccs.201190108. - DOI
    1. Sakin Omer O., Hussein M.A., Hussein B.H.M., Mgaidi A. Adsorption thermodynamics of cationic dyes (methylene blue and crystal violet) to a natural clay mineral from aqueous solution between 293.15 and 323.15 K. Arab. J. Chem. 2018;11:615–623. doi: 10.1016/j.arabjc.2017.10.007. - DOI
    1. Ramezani S., Zahedi P., Bahrami S.-H., Nemati Y. Microfluidic fabrication of nanoparticles based on ethyl acrylate-functionalized chitosan for adsorption of methylene blue from aqueous solutions. J. Polym. Environ. 2019;27:1653–1665. doi: 10.1007/s10924-019-01463-6. - DOI
    1. Yao T., Guo S., Zeng C., Wang C., Zhang L. Investigation on efficient adsorption of cationic dyes on porous magnetic polyacrylamide microspheres. J. Hazard. Mater. 2015;292:90–97. doi: 10.1016/j.jhazmat.2015.03.014. - DOI - PubMed

LinkOut - more resources