Chemical Modification of Bagasse-Based Mesoporous Carbons for Chromium(III) Ion Adsorption

Aims Modified bagasse-based mesoporous carbons were prepared for the efficient chromium(III) ion adsorption and removal from aqueous solutions. Methods Mesoporous carbons were prepared from bagasse with H3PO4 activation and subsequently oxidized with nitric acid and modified with ethylenediamine. Results The results showed that the modified carbon was rich in mesopores, oxygen and nitrogen-containing groups, and the Cr(III) adsorption capacity was greatly improved after modification, which was found to be higher than both pristine and oxidized carbons. The Cr(III) adsorption capacity on modified carbon was significantly influenced by the solution pH, and the optimum pH was 6 with the maximum Cr(III) adsorption capacity up to 24.61mg/g, which was almost 3 times higher than that for pristine carbon. Thermodynamic results manifested the adsorption was spontaneous and endothermic. Kinetic rates fitted the pseudo-second-order model very well. XPS study indicated the amino group was a key factor of the high efficient adsorption.

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Preparation of bio-absorbents by modifying licorice residue via chemical methods and removal of copper ions from wastewater

Water Science & Technology ◽

10.2166/wst.2021.463 ◽

2021 ◽

Author(s):

Xiaochun Yin ◽

Nadi Zhang ◽

Meixia Du ◽

Hai Zhu ◽

Ting Ke

Keyword(s):

Adsorption Capacity ◽

Copper Ions ◽

Order Kinetic ◽

Solution Ph ◽

Chemical Methods ◽

Simple Strategy ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Surface Active ◽

Adsorption Desorption

Abstract In this paper, a series of bio-adsorbents (LR-NaOH, LR-Na2CO3 and LR-CA) were successfully prepared by modifying Licorice Residue with NaOH, Na2CO3 and citric acid, which were used as the adsorbents to remove Cu2+ from wastewater. The morphology and structure of bio-adsorbents were characterized by Fourier Transform Infrared, SEM, TG and XRD. Using static adsorption experiments, the effects of the adsorbent dosage, the solution pH, the adsorption time, and the initial Cu2+ concentration on the adsorption performance of the adsorbents were investigated. The results showed that the adsorption process of Cu2+ by the bio-adsorbents can be described by pseudo-second order kinetic model and the Langmuir model. The surface structure of the LR-NaOH, LR-Na2CO3 and LR-CA changed obviously, and the surface-active groups increased. The adsorption capacity of raw LR was 21.56 mg/g, LR-NaOH, LR- Na2CO3 significantly enhanced this value up to 43.65 mg/g, 43.55 mg/g, respectively. After four adsorption-desorption processes, the adsorption capacity of LR-NaOH also maintained about 73%. Therefore, LR-NaOH would be a promising adsorbent for removing Cu2+ from wastewater, and the simple strategy towards preparation of adsorbent from the waste residue can be as a potential approach using in the water treatment.

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Studies on Copper Ion Adsorption Using Pectin/Functionalized-Silica Coated Cellulose

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1131.210 ◽

2015 ◽

Vol 1131 ◽

pp. 210-214

Author(s):

Radchada Buntem ◽

Thitiwat Tanyalax

Keyword(s):

Hydrochloric Acid ◽

Adsorption Capacity ◽

Filter Paper ◽

Copper Ion ◽

Silica Sol ◽

Ion Adsorption ◽

Functionalized Silica ◽

Solution Ph ◽

Optimum Ph ◽

Sem Micrograph

The pectin/functionalized silica coated filter paper (FILPSL2) was used for copper ion adsorption. Silica sol (1), prepared by mixing ethanol, water, TEOS and hydrochloric acid, was slowly added into pectin solution. A piece of filter paper (2 cm x 2 cm) was immersed in the silica-pectin solution for 1 hr. The coated filter paper was dried at room temperature and then oven-dried at 50 °C for 6 hrs to obtain FILPS. The silica sol (2) was subsequently prepared by mixing ethanol, water, N-[3-(Trimethoxysilyl) propyl] ethylenediamine (L2) and hydrochloric acid. The FILPS was immersed in silica sol (2) and the coated paper was oven-dried at 50 °C for 6 hrs to obtain FILPSL2. The SEM micrograph of uncoated Filter paper (FIL) and FILPSL2 showsa characteristic woven pattern. For copper ion adsorption, FILPSL2 was put into 0.1 M of CuCl2solution (pH 2, 25 °C). The color of the paper changes from off-white to intense blue within 5 min due to the complex between amino group of functionalized silica and Cu2+ as evidenced from IR spectroscopy.The equilibrium adsorption percentage and adsorption capacity were 27.10 and 5.5 x 10-3 respectively. The concentrations of copper ion solutions were varied to 10-2and 10-3M at this pH. The lower concentration of copper ion results in the higher adsorption percentage. While the lower concentration of copper ion results in the lower adsorption capacity. The adsorption was also experimented at pH 3.The similar trend was obtained. The optimum pH for adsorption for all concentrations was 2. The effect of interferences on the copper ion adsorption depends on the pH. At pH 2, Ni2+ has a stronger effect. While Cd2+ has a stronger effect at pH 3. The desorption was performed using 0.2 M CH3COOH solution. The complete desorption occurred within 30 min.

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Dysprosium Removal from Water Using Active Carbons Obtained from Spent Coffee Ground

Nanomaterials ◽

10.3390/nano9101372 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1372 ◽

Cited By ~ 9

Author(s):

Lorena Alcaraz ◽

María Esther Escudero ◽

Francisco José Alguacil ◽

Irene Llorente ◽

Ana Urbieta ◽

...

Keyword(s):

Adsorption Capacity ◽

Potassium Hydroxide ◽

Activated Carbons ◽

Bet Surface Area ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Microporous Material ◽

Spent Coffee Ground ◽

Coffee Ground ◽

Pseudo Second Order

This paper describes the physicochemical study of the adsorption of dysprosium (Dy3+) in aqueous solution onto two types of activated carbons synthesized from spent coffee ground. Potassium hydroxide (KOH)-activated carbon is a microporous material with a specific Brunauer–Emmett–Teller (BET) surface area of 2330 m2·g−1 and pores with a diameter of 3.2 nm. Carbon activated with water vapor and N2 is a solid mesoporous, with pores of 5.7 nm in diameter and a specific surface of 982 m2·g−1. A significant dependence of the adsorption capacity on the solution pH was found, but it does not significantly depend on the dysprosium concentration nor on the temperature. A maximum adsorption capacity of 31.26 mg·g−1 and 33.52 mg·g−1 for the chemically and physically activated carbons, respectively, were found. In both cases, the results obtained from adsorption isotherms and kinetic study were better a fit to the Langmuir model and pseudo-second-order kinetics. In addition, thermodynamic results indicate that dysprosium adsorption onto both activated carbons is an exothermic, spontaneous, and favorable process.

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Characterization of Durian Seed Starch/PVOH Composite Hydrogel as a Potential Adsorbent for Removal of Hazardous Dyes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.931-932.286 ◽

2014 ◽

Vol 931-932 ◽

pp. 286-290 ◽

Cited By ~ 2

Author(s):

W. Pimpa ◽

C. Pimpa

Keyword(s):

Adsorption Capacity ◽

Synthetic Dyes ◽

Order Kinetic ◽

Solution Ph ◽

Environment Friendly ◽

Composite Hydrogels ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Durian Seed

The intention of this study was to prepare the environment friendly durian seed starch/polyvinyl alcohol (DSS/PVOH) composite hydrogels modified by chemical cross-linking with glutaraldehyde and to assess the adsorption potential of the DSS/PVOH composite hydrogels for the removal of the synthetic dyes from aqueous solution. The hydrogels were characterized by swelling behavior and scanning electron microscope (SEM). The effect of DSS content and initial dye solution pH on the adsorption capacity was studied conducting batch experiment system. The DSS/PVOH composite hydrogels consisting 3% DSS has optimum adsorption capacity of 3.411 mg/g (for methylene blue under the condition of pH 7) and 3.274 mg/g (for acid orange 8 under the condition of pH 2.5) at 24 h of contact time. The adsorptions were well fitted by the pseudo-second order kinetic model. It was indicated that the mechanism of removal predominant is effective for low dye concentrations, below 10 mg/l.

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Nascent Rice Husk as an Adsorbent for Removing Cationic Dyes from Textile Wastewater

Applied Sciences ◽

10.3390/app10103437 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3437

Author(s):

Jude Ofei Quansah ◽

Thandar Hlaing ◽

Fritz Ndumbe Lyonga ◽

Phyo Phyo Kyi ◽

Seung-Hee Hong ◽

...

Keyword(s):

Adsorption Capacity ◽

Rice Husk ◽

Textile Wastewater ◽

Cationic Dyes ◽

Adsorption Model ◽

Order Model ◽

Solution Ph ◽

Freundlich Model ◽

Langmuir Isotherm Model ◽

Pseudo Second Order

We assessed the applicability of rice husk (RH) to remove cationic dyes, i.e., methylene blue (MB) and crystal violet (CV), from water. RH thermally treated at 75 °C showed a higher adsorption capacity than that at high temperatures (300–700 °C). For a suitable CV-adsorption model, a pseudo-first-order model for MB adsorption was followed by the kinetics adsorption process; however, a pseudo-second-order model was then suggested. In the qt versus t1/2 plot, the MB line passed through the origin, but that of CV did not. The Langmuir isotherm model was better than the Freundlich model for both dye adsorptions; furthermore, the adsorption capacity for MB and CV was 24.48 mg/g and 25.46 mg/g, respectively. Thermodynamically, the adsorption of both MB and CV onto the RH was found to be spontaneous and endothermic. This adsorption increased insignificantly on increasing the solution pH from 4 to 10. With an increasing dosage of the RH, there was an increase in the removal percentages of MB and CV; however, adsorption capacity per unit mass of the RH was observed to decrease. Therefore, we conclude that utilizing RH as an available and affordable adsorbent is feasible to remove MB and CV from wastewater.

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Mass-transfer processes in the adsorption of crystal violet by activated carbon derived from pomegranate peels: Kinetics and thermodynamic studies

Journal of Engineered Fibers and Fabrics ◽

10.1177/1558925020919847 ◽

2020 ◽

Vol 15 ◽

pp. 155892502091984

Author(s):

Moussa Abbas ◽

Zahia Harrache ◽

Mohamed Trari

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Crystal Violet ◽

Agitation Speed ◽

Second Order ◽

Point Of Zero Charge ◽

Order Kinetic ◽

Solution Ph ◽

Pseudo Second Order ◽

Adsorbent Dose

This study investigates the potential use of activated carbon, prepared from pomegranate peels, as an adsorbent activated using H3PO4 and its ability to remove crystal violet from an aqueous solution. The adsorbent was characterized by the Brunauer–Emmett–Teller method (specific surface area: 51.0674 m2 g−1) and point of zero charge (pHPZC = 5.2). However, some examined factors were found to have significant impacts on the adsorption capacity of activated carbon derived from pomegranate peels such as the initial dye concentration (5–15 mg L−1), solution pH (2–14), adsorbent dose (1–8 g L−1), agitation speed (100–700 r/min), and temperature (298–338 K). The best adsorption capacity was found at pH 11 with an adsorbent dose of 1 g L−1, an agitation speed at 400 r/min, and a contact time of 45 min. The adsorption mechanism of crystal violet onto activated carbon derived from pomegranate peels was studied using the pseudo-first-order, pseudo-second-order, Elovich, and Webber–Morris diffusion models. The adsorption kinetics were found to rather follow a pseudo-second order kinetic model with a determination coefficient ( R2) of 0.999. The equilibrium adsorption data for crystal violet adsorbed onto activated carbon derived from pomegranate peels were analyzed by the Langmuir, Freundlich, Elovich, and Temkin models. The results indicate that the Langmuir model provides the best correlation with qmax capacities of 23.26 and 76.92 mg g−1 at 27°C and 32°C, respectively. The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters like the free energy, enthalpy, and entropy to predict the nature of adsorption process. The negative values Δ G0 (−5.221 to −1.571 kJ mol−1) and Δ H0 (−86.141 kJ mol−1) indicate that the overall adsorption is spontaneous and exothermic with a physisorption process. The adsorbent derived from pomegranate peels was found to be very effective and suitable for the removal of reactive dyes from aqueous solutions, due to its availability, low-cost preparation, and good adsorption capacity.

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Adsorption of Cu(II) by Poly-γ-glutamate/Apatite Nanoparticles

Polymers ◽

10.3390/polym13060962 ◽

2021 ◽

Vol 13 (6) ◽

pp. 962

Author(s):

Kuo-Yu Chen ◽

Wei-Yu Zeng

Keyword(s):

Adsorption Capacity ◽

Kinetic Studies ◽

Maximum Adsorption Capacity ◽

Gravimetric Analysis ◽

Solution Ph ◽

Equilibrium Data ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Initial Adsorption ◽

Adsorption Equilibrium Data

Poly-γ-glutamate/apatite (PGA-AP) nanoparticles were prepared by chemical coprecipitation method in the presence of various concentrations of poly-γ-glutamate (γ-PGA). Powder X-ray diffraction pattern and energy-dispersive spectroscopy revealed that the main crystal phase of PGA-AP was hydroxyapatite. The immobilization of γ-PGA on PGA-AP was confirmed by Fourier transform infrared spectroscopy and the relative amount of γ-PGA incorporation into PGA-AP was determined by thermal gravimetric analysis. Dynamic light scattering measurements indicated that the particle size of PGA-AP nanoparticles increased remarkably with the decrease of γ-PGA content. The adsorption of aqueous Cu(II) onto the PGA-AP nanoparticles was investigated in batch experiments with varying contact time, solution pH and temperature. Results illustrated that the adsorption of Cu(II) was very rapid during the initial adsorption period. The adsorption capacity of PGA-AP nanoparticles for Cu(II) was increased with the increase in the γ-PGA content, solution pH and temperature. At a pH of 6 and 60 °C, a higher equilibrium adsorption capacity of about 74.80 mg/g was obtained. The kinetic studies indicated that Cu(II) adsorption onto PGA-AP nanoparticles obeyed well the pseudo-second order model. The Langmuir isotherm model was fitted well to the adsorption equilibrium data. The results indicated that the adsorption behavior of PGA-AP nanoparticles for Cu(II) was mainly a monolayer chemical adsorption process. The maximum adsorption capacity of PGA-AP nanoparticles was estimated to be 78.99 mg/g.

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Adsorption of lead ions on magnetically separable Fe3O4 watermelon composite

Applied Water Science ◽

10.1007/s13201-020-01307-y ◽

2020 ◽

Vol 10 (10) ◽

Author(s):

Kayode Adebowale ◽

Abisola Egbedina ◽

Blessed Shonde

Keyword(s):

Adsorption Capacity ◽

Scale Up ◽

Lead Ions ◽

X Ray Diffraction ◽

Solution Ph ◽

Freundlich Isotherms ◽

Watermelon Rind ◽

Pseudo Second Order ◽

Polar Interactions ◽

Low Dosage

Abstract The search for green methods for the synthesis of eco-friendly and sustainable materials is the focus of many studies. In this paper, magnetite nanoparticles (WM-Fe3O4) were synthesized using watermelon rind as a stabilizing agent and their adsorption capacity for the removal of lead ions was evaluated. The synthesized WM-Fe3O4 was characterized using Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Adsorption capacity and mechanism of WM-Fe3O4 for the removal of lead ions from water were evaluated. The adsorption isotherms data were well described by both Langmuir and Freundlich isotherms showing the heterogeneous nature of the adsorbent. Adsorption kinetics followed the pseudo-second-order model which confirmed the heterogeneity of the adsorbent and shows that adsorption followed chemisorption. Adsorption capacity was found to be 138 mg/g for lead. The initial solution pH had an influence on the adsorption. The removal efficiency decreased after pH 7. Effect of varying adsorbent mass indicates that a low dosage is required thereby favouring industrial scale up. The adsorption of lead ions was mainly controlled by electrostatic attraction and polar interactions. This adsorbent has potentials for the efficient capture of heavy metals with possibilities for the future replacement of expensive adsorbents.

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Adsorption behavior of Cd2+ ions using hydroxyapatite (HAp) powder

Green Processing and Synthesis ◽

10.1515/gps-2018-0031 ◽

2018 ◽

Vol 7 (5) ◽

pp. 409-416 ◽

Cited By ~ 1

Author(s):

Nguyen Thi Thom ◽

Dinh Thi Mai Thanh ◽

Pham Thi Nam ◽

Nguyen Thu Phuong ◽

Claudine Buess-Herman

Keyword(s):

Heavy Metals ◽

Adsorption Capacity ◽

Negative Impact ◽

Second Order ◽

Solution Ph ◽

First Order ◽

Monolayer Adsorption ◽

Adsorption Data ◽

Intra Particle Diffusion ◽

Pseudo Second Order

Abstract Pollution of heavy metals in water can affect the health of humans and the environment; therefore, removal of heavy metal ions is getting the attention of scientists. To reduce the negative impact of heavy metals on human health and the environment, Cd2+ ions present in water were treated using hydroxyapatite (HAp) as adsorbent. The effects of contact time, initial Cd2+ concentration, solution pH, and adsorbent mass on the adsorption capacity and efficiency of HAp were investigated. Cd2+ uptake was quantitatively evaluated using Langmuir and Freundlich adsorption isotherms. The maximum monolayer adsorption capacity was 119 mg/g. The experimental adsorption data were analyzed using three kinetic models: Lagergren’s pseudo-first-order law, McKay and Ho’s pseudo-second-order law, and the intra-particle diffusion model. The results showed that the Cd2+ removal process follows the pseudo-second-order law.

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Process Optimization and Adsorptive Mechanism for Reactive Blue 19 Dye by Magnetic Crosslinked Chitosan/MgO/Fe3O4 Biocomposite

10.21203/rs.3.rs-836957/v1 ◽

2021 ◽

Author(s):

Ali H. Jawad ◽

Rangabhashiyam S ◽

Ahmed Saud Abdulhameed ◽

Syed Shatir A. Syed-Hassan ◽

Zeid A. ALOthman ◽

...

Keyword(s):

Adsorption Capacity ◽

Freundlich Isotherm ◽

Maximum Adsorption Capacity ◽

Textile Dye ◽

Adsorption Parameters ◽

Solution Ph ◽

Equilibrium Study ◽

Reactive Blue 19 ◽

Pseudo Second Order ◽

Adsorptive Mechanism

Abstract A new biocomposite magnetic crosslinked glutaraldehyde-chitosan/MgO/Fe3O4 (CTS-GL/MgO/Fe3O4) adsorbent was prepared and applied for the removal of reactive blue 19 (RB 19) synthetic textile dye. The prepared CTS-GL/MgO/Fe3O4 was subjected to the several instrumental characterizations such as XRD, FTIR, SEM-EDX, pH-potentiometric titration, and pHpzc analyses. The influence of the input adsorption parameters such as A: CTS-GL/MgO/Fe3O4 dosage, B: initial solution pH, C: process temperature, and D: contact time on RB 19 removal efficiency was statistically optimized using Box-Behnken design (BBD). The analysis of variance (ANOVA) indicates the presence of five significant statistical interactions between input adsorption parameters i.e. (AB, AC, AD, BC, and BD). The adsorption kinetic and equilibrium study reveals a good to the pseudo-second-order model, and multilayer adsorption as proven by Freundlich isotherm model, respectively. The maximum adsorption capacity of CTS-GL/MgO/Fe3O4 towards RB19 was found to be 193.2 mg/g at 45 ºC. This work highlights the development of feasible and recoverable magnetic biocompsite adsorbent with desirable adsorption capacity towards textile dyes with good separation ability by using an external magnetic field.

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