Green Synthesis of pH-Responsive, Self-Assembled, Novel Polysaccharide Composite Hydrogel and Its Application in Selective Capture of Cationic/Anionic Dyes

Dyes are one of the most hazardous chemicals causing significant environmental pollution and affecting water quality. Majority of the existing methods for dye removal and degradation involve synthetic membranes and use of hazardous chemicals, further resulting in secondary pollution. The present study reports polysaccharide based novel composite hydrogel as biodegradable matrix for pH-responsive selective adsorption of cationic/anionic dyes. This membrane showed pH-responsive adsorption of methyl green (MG) and methyl orange (MO) with similar adsorption equilibrium, i.e., 315 and 276 mg g−1, respectively. Interestingly, selective adsorption at different pH has allowed separation of dye mixtures that holds incredible industrial importance for dyes recovery. The hydrogel matrix was able to completely separate MG, a model cationic dye at neutral pH from the dye mixture whereas, it was possible to remove 60% MO, a model anionic dye at acidic pH. Furthermore, comprehensive isothermal and kinetic studies of adsorption revealed that Freundlich isotherm describing the multilayer coverage and pseudo-second-order kinetics were followed. Thermodynamic studies indicated that the adsorption process was spontaneous and endothermic. In fact, the membrane was reusable for at least ten cycles and exhibited desorption efficiency of 80 and 60% for MO and MG, respectively, which may be further recycled to make the process environmentally sustainable. Overall, this study proposes an inexpensive, simple, biologically safe, and efficient adsorbent material for dye effluent treatment.

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pH Triggered superior selective adsorption and separation of both cationic and anionic dyes and photocatalytic activity on a fully exfoliated titanate layer–natural polymer based nanocomposite

Chemical Communications ◽

10.1039/c5cc06214d ◽

2015 ◽

Vol 51 (89) ◽

pp. 16057-16060 ◽

Cited By ~ 23

Author(s):

Amit Kumar Sarkar ◽

Arka Saha ◽

Asit Baran Panda ◽

Sagar Pal

Keyword(s):

Photocatalytic Activity ◽

Selective Adsorption ◽

Dye Adsorption ◽

Natural Polymer ◽

Ph Responsive ◽

Anionic Dyes ◽

Adsorption Desorption

A fully exfoliated titanate–polymer based nanocomposite, with pH responsive selective dye adsorption, desorption and photodegradation properties, is realized.

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Removal of Carcinogenic Dyes Congo red (CR) and Bismarck brown Y (BBY) by Adsorption onto Reusable Hydrogels Derived from Acrylamide

Journal of Physics Conference Series ◽

10.1088/1742-6596/2063/1/012011 ◽

2021 ◽

Vol 2063 (1) ◽

pp. 012011

Author(s):

Huda S Al-Niaeem ◽

Ali A Abdulwahid ◽

Whidad S Hanoosh

Keyword(s):

Experimental Data ◽

Aqueous Solutions ◽

Congo Red ◽

Freundlich Isotherm ◽

Kinetic Studies ◽

Sulphonic Acid ◽

Isotherm Models ◽

Anionic Dyes ◽

Best Fitting ◽

Pseudo Second Order

Abstract Hydrogels of acrylamide (AM), acrylamide\ 2-acrylamido-2-methyl-1-propane sulphonic acid (AMS), and acrylamide\ 2-acrylamido-2-methyl-1-propane sulphonic acid\graphene oxide (AMSGO) were prepared as adsorbents to remove carcinogenic dyes Congo red (CR) and Bismarck brown Y (BBY) from aqueous solutions. Hydrogels were characterized using FSEM and XRD analyses. For both dyes, the synthesized hydrogels demonstrated high adsorption capability at near-neutral pH. Experimental adsorption data were analyzed using the Langmuir and Freundlich isotherm models. It was found that the Langmuir model was more suitable for the experimental data. Kinetic studies found that the pseudo-second-order model demonstrated the best fitting to the experimental data. In addition, thermodynamic studies suggest that the adsorption process was spontaneous and endothermic. The prepared hydrogels were regenerated and reused in four consecutive cycles and it could be applied to remove anionic dyes from aqueous solutions as an effective adsorbent.

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pH-responsive eco-friendly chitosan modified cenosphere/alginate composite hydrogel beads as carrier for controlled release of Imidacloprid towards sustainable pest control

Chemical Engineering Journal ◽

10.1016/j.cej.2021.131215 ◽

2021 ◽

pp. 131215

Author(s):

Amrita Singh ◽

Aditya K. Kar ◽

Divya Singh ◽

Rahul Verma ◽

Nikita Shraogi ◽

...

Keyword(s):

Controlled Release ◽

Pest Control ◽

Composite Hydrogel ◽

Ph Responsive ◽

Hydrogel Beads ◽

Sustainable Pest Control

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Polyaniline and sodium alginate nanocomposite: a pH-responsive adsorbent for the removal of organic dyes from water

RSC Advances ◽

10.1039/d0ra08125f ◽

2020 ◽

Vol 10 (71) ◽

pp. 43904-43914

Author(s):

Deola Majhi ◽

Braja N. Patra

Keyword(s):

Sodium Alginate ◽

Organic Dyes ◽

Selective Removal ◽

Ph Responsive ◽

Anionic Dyes

Polyaniline and sodium alginate nanocomposite was synthesized and it was used for selective removal of both cationic and anionic dyes from water at different pH.

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Husk of Agarwood Fruit-Based Hydrogel Beads for Adsorption of Cationic and Anionic Dyes in Aqueous Solutions

Molecules ◽

10.3390/molecules26051437 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1437

Author(s):

Chih Ming Ma ◽

Bo-Yuan Yang ◽

Gui-Bing Hong

Keyword(s):

Aqueous Solutions ◽

Selective Adsorption ◽

Order Model ◽

Anionic Dyes ◽

Adsorption Selectivity ◽

Hydrogel Beads ◽

Batch System ◽

Initial Ph ◽

Langmuir Isotherm Model ◽

Pseudo Second Order

Hydrogel beads based on the husk of agarwood fruit (HAF)/sodium alginate (SA), and based on the HAF/chitosan (CS) were developed for the removal of the dyes, crystal violet (CV) and reactive blue 4 (RB4), in aqueous solutions, respectively. The effects of the initial pH (2–10) of the dye solution, the adsorbent dosage (0.5–3.5 g/L), and contact time (0–540 min) were investigated in a batch system. The dynamic adsorption behavior of CV and RB4 can be represented well by the pseudo-second-order model and pseudo-first-order model, respectively. In addition, the adsorption isotherm data can be explained by the Langmuir isotherm model. Both hydrogel beads have acceptable adsorption selectivity and reusability for the study of selective adsorption and regeneration. Based on the effectiveness, selectivity, and reusability of these hydrogel beads, they can be treated as potential adsorbents for the removal of dyes in aqueous solutions.

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Preparation and Characterization of Cationized Cellulose for the Removal of Anionic Dyes

Adsorption Science & Technology ◽

10.1260/0263617011494088 ◽

2001 ◽

Vol 19 (3) ◽

pp. 197-210 ◽

Cited By ~ 32

Author(s):

A. Hashem ◽

Reda M. El-Shishtawy

Keyword(s):

Adsorption Capacity ◽

Freundlich Isotherm ◽

Structural Features ◽

Isotherm Models ◽

Acid Orange 7 ◽

Anionic Dyes ◽

Adsorption Parameters ◽

Direct Blue ◽

Equilibrium Data

The factors influencing the cationization of microcrystalline cellulose with 3-chloro-2-hydroxypropyl triethylammonium chloride in the presence of NaOH were investigated. The course of the reaction was followed by estimating the nitrogen content of the cationized product while its structural features were confirmed by IR analysis. The ability of cationized cellulose to adsorb anionic dyes, viz. Acid Orange 7, Direct Blue 75 and Direct Violet 31, was investigated at 25°C and 50°C. The equilibrium data obtained were fitted by the Langmuir and Freundlich isotherm models, allowing the corresponding adsorption parameters to be determined. The results showed that the adsorption capacity was dependent on the adsorbent, temperature, the nature of the dye and (to some extent) on van der Waals and hydrogen bonding. Cationized cellulose exhibited a much better adsorption capacity towards anionic dyes than cellulose.

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Tunable amine-functionalized silsesquioxane-based hybrid networks for efficient removal of heavy metal ions and selective adsorption of anionic dyes

Chemical Engineering Journal ◽

10.1016/j.cej.2021.131370 ◽

2021 ◽

pp. 131370

Author(s):

Qian Ge ◽

Hongzhi Liu

Keyword(s):

Heavy Metal ◽

Metal Ions ◽

Heavy Metal Ions ◽

Selective Adsorption ◽

Hybrid Networks ◽

Efficient Removal ◽

Anionic Dyes ◽

Amine Functionalized

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Adsorption-Kinetic Studies of Mordant Exhaust Dyeing of Cotton and Silk Fabrics with Dye Extract of M. lucida Plant Species

South African Journal of Chemistry ◽

10.17159/0379-4350/2021/v75a16 ◽

2021 ◽

Vol 75 ◽

Author(s):

Janani Loum ◽

Robert Byamukama ◽

P.A.G. Wanyama

Keyword(s):

Adsorption Isotherms ◽

Freundlich Isotherm ◽

Kinetic Studies ◽

Isotherm Models ◽

Freundlich Model ◽

Reaction Orders ◽

Dyed Fabrics ◽

Silk Fabrics ◽

Exhaust Dyeing ◽

Traditional Natural

ABSTRACT The kinetics and adsorption isotherms of the extremely slow traditional natural exhaust dyeing that takes many hours or days have been studied purposely to find means of improving the process. The dyeing of cotton and silk fabrics using dye extract of M. lucida at 50 °C were elucidated with graphs to predict the reaction orders and identify the appropriate adsorption isotherm model(s). Since the dye is UV active, changes in UV absorbance were used in place of changes in concentrations. The simultaneous and post mordanting methods followed pseudo-second-order reactions, hence chemisorption. However, mordant application to the dyed fabrics during post mordant followed a pseudo-first-order model, largely physisorption. Dyeing has followed Langmuir and Freundlich isotherm models with linear correlation r2 ranging between 1 and 0.998. From the Freundlich model and values of Langmuir constant RL (0.9307 to 1.0), the process is homogeneous, forming a favourable and linear monolayer. Accordingly, the dyeing speed can be improved by increasing the concentration of dye liquor. Additionally, according to the Freundlich model, higher dye intensity on fabrics is recorded in post mordanting. Keywords: adsorption isotherms, equilibrium, exhaust dyeing, mordant, rate law

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ADSORPTION AND KINETIC STUDIES OF A NATURAL DYE FROM CURCUMA LONGA L., ONTO BAMBOO YARN

Journal of Chemical Engineering and Industrial Biotechnology ◽

10.15282/jceib.v2i1.3802 ◽

2017 ◽

Vol 2 (1) ◽

pp. 13-26

Author(s):

Tengku Khamanur Azma Tg. Mohd Zamri ◽

Mimi Sakinah Abd Munaim ◽

Zularisam Ab Wahid

Keyword(s):

Adsorption Process ◽

Regression Coefficient ◽

Curcuma Longa ◽

Freundlich Isotherm ◽

Kinetic Studies ◽

Natural Dye ◽

Isotherm Models ◽

Order Model ◽

Dyeing Process ◽

Pseudo Second Order

Natural dye extracted from the rhizome of Curcuma longa L. were applied to bamboo yarns using exhaustion dyeing process. This study investigates the dyeing behaviour of Curcumin; the major color component isolated from rhizomes of Curcuma longa L.on bamboo yarn. Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich isotherm models were used to test the adsorption process of curcumin on bamboo yarn. Comparison of regression coefficient value indicated that the Freundlich isotherm most fitted to the adsorption of curcumin onto bamboo yarn. Furthermore, the kinetics study on this research fitted the pseudo-second order model which indicates that the basis of interaction was chemical adsorption.

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