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Cellulose based pH-sensitive hydrogel for highly efficient dye removal in water treatment: kinetic, thermodynamic, theoretical and computational studies

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Cellulose
Authors:
Loubna Jabir at Mohamed I University
Loubna Jabir
Hayat El Hammi at Mohamed I University
Hayat El Hammi
Nor Mohammed at Abdelmalek Essaâdi University
Nor Mohammed
Issam Jilal at Sidi Mohamed Ben Abdellah University
Issam Jilal
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Abstract and Figures

In this paper, a new green pH-sensitive EDTA crosslinked HEC (cellulose-based hydrogel (swelling rate ~ 1005%)) adsorbent was successfully elaborated. The synthesis of HEC-EDTA at the high advanced crosslinking degree (up to 92%), was carried out using DAEDT and DMAP as acyl transfer agent, where the lamellar morphology (2D-microstructure) was highly suggested based on the average functionality of the reaction system. The crosslinking degree was confirmed using structural analyzes (FTIR and 13C CP/MAS-NMR) and elemental profile analysis. The new EDTA crosslinked HEC demonstrated a high uptake capacity (~ 2000 mg g⁻¹) to aquatic micropollutants, especially methylene blue as cationic dyes model. The kinetic study showed that the adsorption process was well described by the pseudo-second-order kinetic, while the thermodynamic parameters exhibited a negative effect of temperature indicating a physical adsorption process. In addition, the adsorption capacity was studied varying to the experimental conditions (pH, contact time, concentration, etc.), and the Freundlich model revealed a strong correlation to the experimental data indicating an energetic heterogeneity of the surface active sites. Furthermore, using COMPASS II, the molecular dynamics (MD) simulations were conducted to optimize the chemical system, where the results showed the predominance of non-covalent molecular adsorbent-adsorbate interactions, which governs cluster design and configurations.
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Cellulose (2022) 29:4539–4564
https://doi.org/10.1007/s10570-022-04564-z
ORIGINAL RESEARCH
Cellulose based pH‑sensitive hydrogel forhighly efficient
dye removal inwater treatment: kinetic, thermodynamic,
theoretical andcomputational studies
LoubnaJabir· HayatEl‑Hammi· NorMohammed· IssamJilal· AbderrahmaneElIdrissi·
HassanAmhamdi· MohamedAbou‑Salama· YoussefElOuardi· SoufianElBarkany ·
KatriLaatikainen
Received: 5 December 2021 / Accepted: 29 March 2022 / Published online: 21 April 2022
© The Author(s), under exclusive licence to Springer Nature B.V. 2022
temperature indicating a physical adsorption pro-
cess. In addition, the adsorption capacity was studied
varying to the experimental conditions (pH, contact
time, concentration, etc.), and the Freundlich model
revealed a strong correlation to the experimental data
indicating an energetic heterogeneity of the surface
active sites. Furthermore, using COMPASS II, the
molecular dynamics (MD) simulations were con-
ducted to optimize the chemical system, where the
results showed the predominance of non-covalent
molecular adsorbent-adsorbate interactions, which
governs cluster design and configurations.
Keywords Cellulose adsorbent· pH-sensitive
hydrogel· Dyes removal· Water treatment· And
Molecular dynamics
Abstract In this paper, a new green pH-sensitive
EDTA crosslinked HEC (cellulose-based hydrogel
(swelling rate ~ 1005%)) adsorbent was successfully
elaborated. The synthesis of HEC-EDTA at the high
advanced crosslinking degree (up to 92%), was car-
ried out using DAEDT and DMAP as acyl transfer
agent, where the lamellar morphology (2D-micro-
structure) was highly suggested based on the average
functionality of the reaction system. The crosslink-
ing degree was confirmed using structural analyzes
(FTIR and 13C CP/MAS-NMR) and elemental pro-
file analysis. The new EDTA crosslinked HEC dem-
onstrated a high uptake capacity (~ 2000mg g−1) to
aquatic micropollutants, especially methylene blue
as cationic dyes model. The kinetic study showed
that the adsorption process was well described by
the pseudo-second-order kinetic, while the thermo-
dynamic parameters exhibited a negative effect of
L.Jabir(*)· H.El-Hammi· I.Jilal· M.Abou-Salama·
S.ElBarkany(*)
Laboratory ofMolecular Chemistry, Materials
andEnvironment (LMCME), Department ofChemistry,
Faculty Multidisciplinary Nador, Mohamed 1St University,
P. B. 300, 62700Nador, Morocco
e-mail: ja.loubna@gmail.com
S. ElBarkany
e-mail: el.barkany011@gmail.com
N.Mohammed· H.Amhamdi
Applied Chemistry Unit, Sciences andTechnologies
Faculty, Abdelmalek Essaadi University,
32003AlHoceima, Morocco
A.ElIdrissi
Laboratory Applied Chemistry andEnvironmental
(LCAE-URAC18), Faculty ofSciences ofOujda,
Mohamed1stUniversity, 60000Oujda, Morocco
Y.ElOuardi
LIMOME Laboratory, Faculty ofSciences Dhar El
Mehraz, Sidi Mohamed Ben Abdellah University, Dhar El
Mehraz B.P. 1796 Atlas, 30000Fes, Morocco
Y.ElOuardi· K.Laatikainen
Laboratory ofSeparation Technology, Lappeenranta
University ofTechnology, P.O. Box20,
53851Lappeenranta, Finland
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... pH-responsive hydrogel offers a larger surface area during swelling. This allows more contaminated solutions to come into contact with the hydrogel, improving pollutant removal efficiency (Jabir et al., 2022). For example, Wang et al. developed a pH-responsive carboxymethyl cellulose/chitosan hydrogel for adsorbing and desorbing anionic and cationic dyes. ...
... The hydrogel exhibited reusability for up to seven cycles with very minimal loss of adsorption capacity (Singh et al., 2019). Jabir et al. demonstrated impressive dye removal with cellulose-based hydrogel (Jabir et al., 2022). These studies underscore the effectiveness of pH-responsive hydrogel, enabling efficient desorption of pollutants and hydrogel regeneration for multiple uses (Li et al., 2023). ...
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... To enhance the adsorption efficiency, chelating functional groups can be grafted onto the surface of the adsorbent (Li et al. 2009;Pourjavadi et al. 2009;Zhao et al. 2019). Several studies have shown that HEC functionalized with organic compounds and polymers like Ethylenediaminetetraacetic acid (EDTA) and poly (acrylic acid) (PAA) can significantly increase the elimination capacity of valuable metal ions (Cavus et al. 2006;Jilal et al. 2018Jilal et al. , 2019Jabir et al. 2022). However, certain properties need to be fine-tuned to optimize the adsorbing properties of modified HEC. ...
... Recently, numerous studies have aimed to mitigate the ecological impacts of water pollution by utilizing biodegradable materials for adsorption (Jabir et al. 2022;Al-Gethami et al. 2024). Pollution from heavy metals and industrial dyes is particularly concerning due to their high toxicity and persistence in the environment. ...
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... In fact, it has been reported that nano-hydroxyapatite exhibits rapid elimination efficiency for all MB concentrations which is important for wastewater treatment application (Swamiappan et al., 2021). Moreover, the lack of internal diffusion resistance may be responsible for the high rate of adsorption (Jabir et al., 2022). Various starting MB concentrations were tested for their effects on adsorption equilibrium time, and the results indicated that these initial MB concentrations had little to no impact on this time. ...
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