Modified lignin nanosphere adsorbent for lead and copper ions

Heavy metal ions in wastewater have negative effects on humans and the environment. In this paper, the adsorption of lead and copper ions by modified eucalyptus lignin nanosphere (ECLNPs) was studied. The spherical alkali-lignin particles had a diameter of 50 nm, abundant carboxyl groups of 0.66 mmol/g, and relatively high adsorption performance. The equilibrium adsorption capacities of Pb(II) and Cu(II) by ECLNPs were 126.0 mg/g and 54.4 mg/g, respectively. Both Pb(II) and Cu(II) adsorptive processes fitted a pseudo-second-order kinetics model. In the simultaneous adsorption process of Pb(II) and Cu(II), ECLNPs had higher adsorptive selectivity for Pb(II) than Cu(II), and there was a competitive adsorption process between Pb(II) and Cu(II). This resulted from the lower hydration heat of Pb(II) in water, which leads to easier separation from water ligands. ECLNPs also showed good recyclability, with 16.6% and 21.1% loss in Pb(II) and Cu(II) adsorption capacity, respectively, after three consecutive adsorption-desorption cycles, which provides a feasible technical direction for the utilization of biomass resources and the treatment of water contamination.

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Enhancing acidic dye adsorption by modified UiO-66

Journal of Applied Materials and Technology ◽

10.31258/jamt.1.2.54-62 ◽

2020 ◽

Vol 1 (2) ◽

pp. 54-62

Author(s):

Naser Al Amery ◽

Hussein Rasool Abid ◽

Shaobin Wang ◽

Shaomin Liu

Keyword(s):

Adsorption Process ◽

Dye Adsorption ◽

Batch Adsorption ◽

First Order ◽

Freundlich Isotherms ◽

Adsorption Capacities ◽

Pseudo Second Order ◽

The Stability ◽

Second Order Equations ◽

Better Than

In this study, two improved versions of UiO-66 were successfully synthesised. Modified UiO-66 and UiO-66-Ce were characterised to confirm the integrity of the structure, the stability of functional groups on the surface and the thermal stability. Activated samples were used for removal harmful anionic dye (methyl orange) (MO) from wastewater. Batch adsorption process was relied to investigate the competition between those MOFs for removing MO from aqueous solution. Based on the results, at a higher initial concentration, the maximum MO uptake was achieved by UiO-66-Ce which was better than modified-UiO-66. They adsorbed 71.5 and 62.5 mg g-1 respectively. Langmuir and Freundlich isotherms were employed to simulate the experimental data. In addition, Pseudo first order and Pseudo second order equations were used to describe the dynamic behaviour of MO through the adsorption process. The high adsorption capacities on these adsorbents can make them promised adsorbents in industrial areas.

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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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Recovery of phosphate from aqueous solution by magnetically recycled modified polishing powder composites

Water Science & Technology ◽

10.2166/wst.2019.381 ◽

2019 ◽

Vol 80 (7) ◽

pp. 1357-1366

Author(s):

Jianming Liu ◽

Runying Bai ◽

Junfeng Hao ◽

Bowen Song ◽

Yu Zhang ◽

...

Keyword(s):

Adsorption Capacity ◽

Ligand Exchange ◽

Adsorption Process ◽

High Adsorption ◽

Order Model ◽

Powder Composites ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Ph Level ◽

Adsorption Desorption

Abstract This study investigated a magnetically recycled modified polishing powder (CMIO@PP) as an adsorbent of phosphate; the CMIO@PP was synthesized by combining the modified La/Ce-containing waste polishing powder with CaO2-modified Fe3O4 (CMIO). Results indicate that the CMIO@PP nanocomposite presents a crystal structure comprising La (OH)3, Ce (OH)3, and Fe3O4, and that CMIO is uniformly dispersed in the modified polishing powder. The CMIO@PP (1:3) is a suitable choice considering its magnetism and adsorption capacity. The magnetic adsorbent exhibits a high adsorption capacity of 53.72 mg/g, a short equilibrium time of 60 min, and superior selectivity for phosphate. Moreover, the adsorbent strongly depends on the pH during the adsorption process and maintains a large adsorption capacity when the pH level is between 2 and 6. The adsorption of phosphate by the CMIO@PP (1:3) accords with the Langmuir isotherm model, and the adsorption process follows the pseudo-second order model. Meanwhile, adsorption–desorption experiments show that the adsorbent could be recycled a few times and that a high removal efficiency of phosphate from civil wastewater was achieved. Finally, mechanisms show that the adsorption of phosphate by the CMIO@PP (1:3) is mainly caused by electrostatic attraction and ligand exchange.

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Adsorption of Copper Ions from Wastewater by Carboxymethylcellulose Sulfate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.393-395.1098 ◽

2011 ◽

Vol 393-395 ◽

pp. 1098-1101 ◽

Cited By ~ 2

Author(s):

Yan Yu ◽

Feng Yuan Huang

Keyword(s):

Contact Time ◽

Copper Concentration ◽

Adsorption Process ◽

Ph Value ◽

Copper Ions ◽

Adsorption Capacities ◽

Monolayer Adsorption ◽

Optimum Ph ◽

Equilibrium Data ◽

Langmuir Isotherm Model

In the present paper, the ability of carboxymethylcellulose sulfate (CMC-S) for Cu(II) removal was studied. The influence of factors, such as the pH value, the initial copper concentrations, and the contact time, were investigated in detail. Atomic absorption spectrophotometer was applied to determined the concentration of Cu(II). The results showed that the adsorption process was strongly dependent on the pH value and the initial copper concentration. The optimum pH value was in the range of 6-7. The theoretical adsorption capacities for Cu(II) was 127.7 mg/g. The equilibrium data was well fitted to the Langmuir isotherm model at 25°C, which can be explained as a monolayer adsorption.

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Equilibrium and Kinetic study of lead and copper ions adsorption on Chitosan-grafted-poly acrylic acid synthesized by Surface-initiated Atomic Transfer Polymerization

10.20944/preprints201806.0260.v1 ◽

2018 ◽

Author(s):

Carlos Grande ◽

William Vallejo ◽

Fabio Zuluaga

Keyword(s):

Acrylic Acid ◽

Adsorption Process ◽

Adsorption Equilibrium ◽

Copper Ions ◽

Surface Adsorption ◽

Toxic Metal ◽

Maximum Adsorption Capacity ◽

Equilibrium Studies ◽

Adsorption Capacities ◽

Poly Acrylic Acid

In this work, we synthesized chitosan grafted-poly acrylic acid (CS-g-PA) through surface-initiated atom transfer radical polymerization (SI-ATRP). We also studied the adsorption process of copper and lead ions onto CS-g-PA surface. Adsorption equilibrium studies indicated pH 4.0 as the best pH for the adsorption process, while the maximum adsorption capacity for Pb2+ ions was 98 mg*g-1 and for Cu2+ was 164 mg*g-1, higher adsorption capacities than chitosan alone (CS), where Pb2+ was only 14.8 mg*g-1and Cu2+ was 140 mg*g-1, respectively. Furthermore, the adsorption studies indicated that Langmuir model describes all the experimental data. All these results suggest that the new CS-g-PA polymers had potential as adsorbent for hazardous and toxic metal ions produced by different industries.

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High Removal Efficiency of Diatomite-Based X Zeolite for Cu2+ and Zn2+

Materials ◽

10.3390/ma14216525 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6525

Author(s):

Guangyuan Yao ◽

Yuqiang Liu ◽

Shuilin Zheng ◽

Ya Xu

Keyword(s):

Ion Exchange ◽

Adsorption Process ◽

Interface Properties ◽

Order Model ◽

Adsorption Capacities ◽

Adsorption Data ◽

X Zeolite ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Kinetics And Isotherms

Diatomite-based X zeolite was obtained and its crystallinity, morphology, and interface properties were investigated by XRD, BET, SEM, EDS, and XRF. The obtained X zeolite possessed a unique meso-microporous structure and showed good ion exchange properties for Cu2+ and Zn2+. The pseudo-second-order model and Langmuir isotherm model can best describe the adsorption kinetics and isotherms of Cu2+ and Zn2+, respectively. The maximal adsorption capacities of X zeolite for Cu2+ and Zn2+ were 146 and 195 mg/g at 323 K, respectively. Meanwhile, the adsorption process for Cu2+ and Zn2+ were chemical adsorption and ion exchange, respectively. Furthermore, the adsorption data turned out to be an endothermic and spontaneous process. Compared with other reported materials, the adsorption capacity of X zeolite synthesized from diatomite was among the highest. Therefore, it could be a promising adsorbent for the disposal of wastewater that contains metal ions.

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Microstructural and Equilibrium Adsorption Study of the System of Waste Foundry Molding Sand/Cu (II) Ions

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0292 ◽

2016 ◽

Vol 61 (4) ◽

pp. 1805-1812

Author(s):

A. Strkalj ◽

Z. Glavas ◽

L. Slokar

Keyword(s):

Experimental Data ◽

Adsorption Process ◽

Order Kinetic ◽

Molding Sand ◽

Adsorption Study ◽

Eds Analysis ◽

Adsorption Capacities ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Casting Production

Abstract This paper deals with the waste foundry molding sand which originally comes from the casting production. Adsorption of Cu (II) ions on the waste foundry molding sand was studied. Experimental data were processed using adsorption isotherms. Obtained results show that the experimental data are best described by the Langmuir isotherm. The following adsorption capacities are obtained: 7.153 mg/g to 293 K, 8.403 mg/g at 333 K and 9.208 mg/g at 343 K. The kinetics and thermodynamics of the process were analysed. The obtained results indicate that the adsorption process takes place according to the pseudo second order kinetic model with the following constants: 0.438 g/mg min at 293 K, 0.550 g/mg min at 333 K and 1.872 g/mg min at 343 K. The following values of ΔG° were obtained: − 95.49 J/mol at 293 K, − 736.99 J/mol at 333 K and − 1183.46 J/mol at 343 K. The value of ΔH° is − 4.16 kJ/mol and the value of ΔS° is 15.17 J/molK. These results were confirmed by microscopic examinations. The results indicate that the adsorption process of Cu (II) ions on waste foundry molding sand is possible. Results of microscopic examinations show the homogeneity of the surface, which is proof of the chemisorption. Cu (II) ions on the surface of the waste foundry molding sand were detected after adsorption by EDS analysis, which proves the existence of the adsorption process.

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A slow pyrolysis biochar derived from Tetrapanax papyriferum petiole as an effective sorbent for removing copper ions from aqueous solution

BioResources ◽

10.15376/biores.14.2.4430-4453 ◽

2019 ◽

Vol 14 (2) ◽

pp. 4430-4453

Author(s):

Wenqi Li ◽

Liping Zhang ◽

Ying Guan ◽

Zhihan Tong ◽

Xiang Chen ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Mechanism ◽

Adsorption Process ◽

Copper Ions ◽

Maximum Adsorption Capacity ◽

Transmission Electron ◽

Tetrapanax Papyriferum ◽

Pseudo Second Order ◽

Nanopore Structure ◽

Effective Sorbent

Biochar derived from Tetrapanax papyriferum petioles at different pyrolysis temperatures was used to remove copper from aqueous solution. Abundant porous structures were observed with scanning electron microscopy, and transmission electron microscope images revealed a unique layered nanopore structure. A high pyrolytic temperature resulted in a biochar with a higher surface area, ash content, and mineral element content. The maximum adsorption capacity of T. papyriferum petiole biochar (TBC) was 182 mg/g. The Langmuir adsorption isotherm model and pseudo-second-order kinetics model were most suitable for describing the adsorption process, indicating that adsorption takes place at specific homogeneous sites within the adsorbent. The calculated ΔH° values indicated that the adsorption process was endothermic. The adsorption mechanism for TBC was attributed to precipitation, ion exchange, C-π interactions, and complexation. Thus, the biochar used in this study is a promising environmentally friendly and effective adsorbent for removing Cu2+ ions from an aqueous solution.

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Preparation of hydrogel reinforced with bentonite by gamma irradiation for metal absorption

Nuclear Science and Technology ◽

10.53747/jnst.v10i4.15 ◽

2021 ◽

Vol 10 (4) ◽

pp. 48-55

Author(s):

Tran To Uyen ◽

Trinh Thi Tu Anh ◽

Tamikazu Kume ◽

Cao Dong Vu ◽

Nguyen Minh Hiep ◽

...

Keyword(s):

Gamma Irradiation ◽

Adsorption Process ◽

Absorption Spectrometry ◽

Order Model ◽

Adsorption Capacities ◽

Dose Concentration ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Aas Method ◽

Irradiation Technology

A natural-based sodium carboxymethyl cellulose (CMC) hydrogel reinforced with bentonite was prepared by using gamma irradiation technology. This is a novel hydrogel that uses natural polymer to absorb metal ions in wastewater. The influence of dose, concentration of CMC and bentonite on the sorption of hydrogels was investigated by atomic absorption spectrometry (AAS) method. According to the Langmuir isotherm model, the maximum adsorption capacities of CMC/bentonite hydrogel for Cu2+ and Pb2+ were 181.82 mg/g and 204.08 mg/g at room temperature, respectively. The pseudo-second-order model which describes the adsorption process of Cu2+ and Pb2+ was also studied

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Adsorption of chlorinated acetic acids by quaternary ammonium cationic cellulose

Water Science & Technology Water Supply ◽

10.2166/ws.2013.208 ◽

2013 ◽

Vol 14 (2) ◽

pp. 321-328 ◽

Cited By ~ 1

Author(s):

Wenjian Shi ◽

Haixin Gu ◽

Xuan Chen ◽

Yuanxing Huang ◽

Wei Wu ◽

...

Keyword(s):

Quaternary Ammonium ◽

Adsorption Process ◽

Physical Adsorption ◽

Dichloroacetic Acid ◽

Trimethylammonium Chloride ◽

Monomolecular Layer ◽

Adsorption Capacities ◽

Adsorption Processes ◽

Pseudo Second Order ◽

Acetic Acids

Etherifying agent, 3-chloro-2-hydroxypropyl trimethylammonium chloride (CHPTA) was modified by grafting on cellulose to make quaternary ammonium cationic cellulose (QACC) with 2.01% nitrogen content and a degree of substitution of 0.289. The experiment results showed that at 318 K, the adsorption capacities of QACC on monochloroacetic acid (MCAA), dichloroacetic acid and trichloroacetic acid (TCAA) were 1.80, 1.87 and 2.01 mmol/g, respectively. The adsorption process could be modeled by pseudo second-order kinetics very well. The adsorption rate constant increased with temperature, and the adsorption pattern fitted Langmuir isotherms, which was monomolecular layer absorption. ΔH of the three chlorinated acetic acids were all above zero, and ΔS of them were above zero too. At 298 K, ΔG of the adsorption processes were below zero. These experiment results showed that it was main chemical adsorption accompanied by physical adsorption.

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