Preparation, Performances and Mechanisms of Co@AC Composite for Herbicide Atrazine Removal in Water

In this study, a high-performance adsorbent Co@AC was prepared by loading cobalt ions (Co2+) on activated carbon (AC) via solution impregnation and high-temperature calcination technology, and was used to remove atrazine in water. The preparation factors on the adsorbent properties were studied, and the characteristics were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectrometer (FTIR). The results showed that Co@AC possessed the best performance when the factors were 7.0% of Co2+ (w/v), 7.0 h of immersing time, 500 °C of calcination temperature and 4.0 h of calcination time. The adsorption conditions and mechanisms for atrazine removal by Co@AC were also studied scientifically. As the conditions were pH 4.0, reaction time 90 min and temperature 25 °C, Co@AC had the largest adsorption capacity, which was 92.95 mg/g, and the maximum removal rate reached 94.79%. The correlation coefficient of the Freundlich isotherm was better than that of the Langmuir isotherm, and the adsorption process followed the pseudo-second-order kinetic model. Cycle experiments showed that the removal efficiency of atrazine by Co@AC remained above 85% after five repeated experiments, indicating that Co@AC showed a strong stable performance and is a promising material for pesticides removal.

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Loess Based Copolymer Composite for Removing Basic Fuchsin

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.633.165 ◽

2014 ◽

Vol 633 ◽

pp. 165-168 ◽

Cited By ~ 2

Author(s):

Li Wang ◽

Wen Juan He ◽

Yu Feng He ◽

Hong Li ◽

Rong Min Wang

Keyword(s):

Kinetic Model ◽

Optimal Condition ◽

Removal Rate ◽

Freundlich Isotherm ◽

Order Kinetic ◽

Basic Fuchsin ◽

Adsorption Dynamics ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Polymer Adsorbent

Loess based copolymer (L/CoPolym), a typical silicate minerals / copolymer composite, was used as polymer adsorbent for removing basic fuchsin (BF) in wastewater. Under the optimal condition of adsorption, the removal rate of BF reached to 98.2%, and the adsorption capacity got to 565.0 mg/g. Adsorption dynamics were consistent with pseudo-second-order kinetic model and isotherm model can meet the Freundlich isotherm.

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Sawdust for the Removal of Heavy Metals from Water: A Review

Molecules ◽

10.3390/molecules26144318 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4318

Author(s):

Elie Meez ◽

Abbas Rahdar ◽

George Z. Kyzas

Keyword(s):

Heavy Metals ◽

Adsorption Mechanism ◽

Freundlich Isotherm ◽

Order Kinetic ◽

Suitable Material ◽

Removal Of Heavy Metals ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

And Control ◽

Environmental Agencies

The threat of the accumulation of heavy metals in wastewater is increasing, due to their abilities to inflict damage to human health, especially in the past decade. The world’s environmental agencies are trying to issue several regulations that allow the management and control of random disposals of heavy metals. Scientific studies have heavily focused on finding suitable materials and techniques for the purification of wastewaters, but most solutions have been rejected due to cost-related issues. Several potential materials for this objective have been found and have been compared to determine the most suitable material for the purification process. Sawdust, among all the materials investigated, shows high potential and very promising results. Sawdust has been shown to have a good structure suitable for water purification processes. Parameters affecting the adsorption mechanism of heavy metals into sawdust have been studied and it has been shown that pH, contact time and several other parameters could play a major role in improving the adsorption process. The adsorption was found to follow the Langmuir or Freundlich isotherm and a pseudo second-order kinetic model, meaning that the type of adsorption was a chemisorption. Sawdust has major advantages to be considered and is one of the most promising materials to solve the wastewater problem.

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The Removal of Uranium and Thorium from Their Aqueous Solutions by 8-Hydroxyquinoline Immobilized Bentonite

Minerals ◽

10.3390/min9100626 ◽

2019 ◽

Vol 9 (10) ◽

pp. 626 ◽

Cited By ~ 2

Author(s):

Salah ◽

Gaber ◽

Kandil

Keyword(s):

Aqueous Solutions ◽

Metal Ions ◽

Langmuir Isotherm ◽

Freundlich Isotherm ◽

Order Kinetic ◽

X Ray Diffraction ◽

Solution Ph ◽

X Ray ◽

Order Kinetic Model ◽

Pseudo Second Order

The sorption of uranium and thorium from their aqueous solutions by using 8-hydroxyquinoline modified Na-bentonite (HQ-bentonite) was investigated by the batch technique. Na-bentonite and HQ-bentonite were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier Transform Infrared (FTIR) spectroscopy. Factors that influence the sorption of uranium and thorium onto HQ-bentonite such as solution pH, contact time, initial metal ions concentration, HQ-bentonite mass, and temperature were tested. Sorption experiments were expressed by Freundlich and Langmuir isotherms and the sorption results demonstrated that the sorption of uranium and thorium onto HQ-bentonite correlated better with the Langmuir isotherm than the Freundlich isotherm. Kinetics studies showed that the sorption followed the pseudo-second-order kinetic model. Thermodynamic parameters such as ΔH°, ΔS°, and ΔG° indicated that the sorption of uranium and thorium onto HQ-bentonite was endothermic, feasible, spontaneous, and physical in nature. The maximum adsorption capacities of HQ-bentonite were calculated from the Langmuir isotherm at 303 K and were found to be 63.90 and 65.44 for U(VI) and Th(IV) metal ions, respectively.

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The Presence of Cu Facilitates Adsorption of Tetracycline (TC) onto Water Hyacinth Roots

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15091982 ◽

2018 ◽

Vol 15 (9) ◽

pp. 1982 ◽

Cited By ~ 1

Author(s):

Xin Lu ◽

Beibei Tang ◽

Qi Zhang ◽

Lizhu Liu ◽

Ruqin Fan ◽

...

Keyword(s):

Water Hyacinth ◽

Freundlich Isotherm ◽

Root Surface ◽

Interactive Effects ◽

Order Kinetic ◽

Batch Experiments ◽

Adsorption Data ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Ph Range

Batch experiments were conducted to investigate the adsorption characteristics of tetracycline (TC), and the interactive effects of copper (Cu) on the adsorption of TC onto water hyacinth roots. TC removal efficiency by water hyacinth roots was ranging from 58.9% to 84.6%, for virgin TC, 1:1 TC-Cu and 1:2 TC-Cu. The Freundlich isotherm model and the pseudo-second-order kinetic model fitted the adsorption data well. Thermodynamics parameters ΔG0 for TC were more negative in the TC plus Cu than the TC-only treatments, indicating the spontaneity of TC adsorption increased with increasing of Cu concentrations. An elevated temperature was associated with increasing adsorption of TC by water hyacinth roots. The additions of Cu(II) significantly increased TC adsorption onto water hyacinth roots within the pH range 4 to 6, because copper formed a strong metal bridge between root surface and TC molecule, facilitating the adsorption of TC by roots. However, Cu(II) hindered TC adsorption onto water hyacinth roots on the whole at pH range from 6–10, since the stronger electrostatic repulsion and formation of CuOH+ and Cu(OH)2. Therefore, the interaction between Cu(II) and TC under different environmental conditions should be taken into account to understand the environmental behavior, fate, and ecotoxicity of TC.

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Construction of Novel Polymerizable Ionic Liquid Microemulsions and the In Situ Synthesis of Poly(Ionic Liquid) Adsorbents

Nanomaterials ◽

10.3390/nano9030454 ◽

2019 ◽

Vol 9 (3) ◽

pp. 454 ◽

Cited By ~ 2

Author(s):

Aili Wang ◽

Shuhui Li ◽

Hou Chen ◽

Ying Liu ◽

Xiong Peng

Keyword(s):

Ionic Liquid ◽

Adsorption Process ◽

Freundlich Isotherm ◽

In Situ Synthesis ◽

Scattering Data ◽

Order Kinetic ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Poly Ionic Liquid

This paper reports the successful construction of novel polymerizable ionic liquid microemulsions and the in situ synthesis of poly(ionic liquid) adsorbents for the removal of Zn2+ from aqueous solution. Dynamic light-scattering data were used to confirm the polymerization media and to illustrate the effect of the crosslinker dosage on the droplet size of the microemulsion. FTIR and thermal analysis were employed to confirm the successful preparation of the designed polymers and characterize their thermostability and glass transition-temperature value. The optimization of the adsorption process indicates that the initial concentration of Zn2+, pH, adsorbent dosage and contact time affected the adsorption performance of poly(ionic liquid)s toward Zn2+. Furthermore, our research revealed that the adsorption process can be effectively described by the pseudo second-order kinetic model and the Freundlich isotherm model.

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Removal of fluoride from aqueous solution by adsorption onto Kanuma mud

Water Science & Technology ◽

10.2166/wst.2010.472 ◽

2010 ◽

Vol 62 (8) ◽

pp. 1888-1897 ◽

Cited By ~ 8

Author(s):

Nan Chen ◽

Zhenya Zhang ◽

Chuanping Feng ◽

Miao Li ◽

Rongzhi Chen ◽

...

Keyword(s):

Adsorption Process ◽

Fluoride Concentration ◽

Freundlich Isotherm ◽

Order Kinetic ◽

Solution Ph ◽

Intra Particle Diffusion ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Solid Liquid Interface ◽

Solid Liquid

Kanuma mud, a geomaterial, is used as an adsorbent for the removal of fluoride from water. The influences of contact time, solution pH, adsorbent dosage, initial fluoride concentration and co-existing ions were investigated by batch equilibration studies. The rate of adsorption was rapid with equilibrium being attained after about 2 h, and the maximum removal of fluoride was obtained at pH 5.0–8.0. The Freundlich isotherm model was found to represent the measured adsorption data well. The negative value of the thermodynamic parameter ΔG suggests the adsorption of fluoride by Kanuma mud was spontaneous, the endothermic nature of adsorption was confirmed by the positive ΔH value. The negative ΔS value for adsorbent denoted decreased randomness at the solid/liquid interface. The adsorption process using Kanuma mud followed the pseudo-second-order kinetic model. Fluoride uptake by the Kanuma mud was a complex process and intra-particle diffusion played a major role in the adsorption process. It was found that adsorbed fluoride could be easily desorbed by washing the adsorbent with a solution of pH 12. This indicates the material could be easily recycled.

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Removal of Rhodamine B from Wastewater by Rectorite and Sepiolite-Kinetic Study and Equilibrium Isotherm Analyses

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.183-185.362 ◽

2011 ◽

Vol 183-185 ◽

pp. 362-366 ◽

Cited By ~ 1

Author(s):

Jun Li ◽

Ming Zhen Hu

Keyword(s):

Rhodamine B ◽

Low Cost ◽

Freundlich Isotherm ◽

Second Order ◽

Order Kinetic ◽

Isotherm Equation ◽

Adsorption Removal ◽

Equilibrium Data ◽

Order Kinetic Model ◽

Pseudo Second Order

Adsorption removal of a cationic dye, rhodamine B (RhB) from water onto rectorite and sepiolite was investigated. The rectorite and sepiolite were characterized by Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). Attempts were made to fit the isothermal data using Langmuir and Freundlich equations. The experimental results have demonstrated that the equilibrium data are fitted well by a Freundlich isotherm equation. Pseudo-first-order and pseudo-second-order models were considered to evaluate the rate parameters. The experimental data were well described by the pseudo-second-order kinetic model. The results indicate that the rectorite exhibited higher adsorption capacity for the removal of RhB than sepiolite and could be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes.

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Removal of antibiotic Ciprofloxacin Hydrochloride from water by Kandira stone: Kinetic models and thermodynamic

Global NEST Journal ◽

10.30955/gnj.001604 ◽

2015 ◽

Vol 17 (3) ◽

pp. 498-507 ◽

Cited By ~ 3

Keyword(s):

Freundlich Isotherm ◽

Entropy Change ◽

Building Stone ◽

Order Kinetic ◽

Sorption Data ◽

Ciprofloxacin Hydrochloride ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Rate Controlling Step ◽

Cladding Material

<div> In this study, Kandira stone, extensively used as a cladding material for building stone has been examined for the removal of an antibiotic Ciprofloxacin hydrochloride (CIP) from its aqueous solution. Batch experiments were performed to investigate the adsorption kinetics, equilibrium and thermodynamics between the adsorbent surfaces and CIP. The sorption data follows Freundlich isotherm. A chemical adsorption was dominant. The adsorption behaviour of CIP onto Kandira stone followed the pseudo-second-order kinetic model, indicating that the adsorption process can be expressed with the chemisorption mechanism. The intraparticle diffusion process is a rate-controlling step. The adsorption thermodynamic parameters of the free energy change (∆Go), the isosteric enthalpy change (∆Ho) and the entropy change (∆So) were calculated. The negative ∆Ho values indicated that sorption of CIP was the exothermic process. The positive value of ∆Go indicates non-spontaneous nature of CIP adsorption.  </div>

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Adsorption Behaviour of Chromium(VI) onto Surface Modified Sugarcane Waste

Tribhuvan University Journal ◽

10.3126/tuj.v28i1-2.26230 ◽

2013 ◽

Vol 28 (1-2) ◽

pp. 113-122

Author(s):

Kedar Nath Ghimire ◽

Deepak Wagle ◽

Suman Lal Shrestha

Keyword(s):

Volume Ratio ◽

Freundlich Isotherm ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Adsorption Method ◽

Chromium Vi ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Surface Modified

An effective chemically modified adsorbent based on sugarcane waste has been prepared by treating with concentrated sulphuric acid in 2:1weight/volume ratio. Thus prepared adsorbent has been found to be effective in the adsorption of chromium from aqueous medium. The efficacy of the adsorbent in the removal of chromium was evaluated by batch adsorption method. The effect of initial concentration, contact time and pH of the solution was investigated. The maximum adsorption capacity onto this adsorbent was found to be 195 mg/g at their optimal pH 1 at which unmodified bagasse has only 58 mg/g. The characterization of adsorbent was done by determining surface area and Boehm’s titration method. Freundlich isotherm and pseudo-second order kinetic model gave better explanation of the adsorption process.

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From coordination polymer to carbon nanotube: Preparation, characterization and rapid adsorption capacity toward organic pollutants

Journal of Chemical Research ◽

10.1177/1747519820907562 ◽

2020 ◽

Vol 44 (7-8) ◽

pp. 487-493

Author(s):

Hong-Yan Lin ◽

Yi-Fei Wang ◽

Yuan Tian ◽

Guo-Cheng Liu ◽

Jian Luan

Keyword(s):

Carbon Nanotubes ◽

Coordination Polymer ◽

High Performance ◽

Low Cost ◽

Freundlich Isotherm ◽

Catalyst Precursor ◽

Order Kinetic ◽

Order Kinetic Model ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

A CuI coordination polymer based on the N,N’-bis(3-pyridinecarboxamide)-1,4-butane (3-dpyb) ligand, namely [Cu(3-dpyb)0.5Cl], is hydrothermally synthesized and structurally characterized, and is used as a catalyst precursor to synthesize multi-walled carbon nanotubes. Interestingly, the as-grown multi-walled carbon nanotubes exhibit high performance in removing dyes from solution and can serve as a low-cost and fast adsorbent. In addition, the adsorption behavior of this new adsorbent fits well with the Freundlich isotherm and the pseudo-second-order kinetic model.

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