scholarly journals Separation of copper ions by nanocomposites using adsorption process

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nasim Danesh ◽  
Mohsen Ghorbani ◽  
Azam Marjani

AbstractIn this research, a novel nanocomposite adsorbent, graphene oxide modified with magnetite nanoparticles and Lauric acid containing ethylenediaminetetraacetic acid (GFLE) has been applied for the eliminate of Cu2+ ions. Adsorption performance was considered as a function of solution pH, Cu2+ ions concentration (C Cu2+), and temperature (T) and contact time (t). The levels of each variable were statistically optimized by Central Composite Design (CCD) and the response surface methodology (RSM) procedure to enhance the yield of system design. In these calculations, Y was measured as the response (the secondary concentration of Cu2+ ions in mg L−1). Highest copper adsorption occurred at time of 105 min, temperature of 40 °C, the initial concentration of 280 mg L−1, and pH = 1. The sorption equilibrium was well demonstrated using the Freundlich isotherm model. The second-order kinetics model suggested that the sorption mechanism might be ion exchange reactions. Thermodynamic factors and activation energy values displayed that the uptake process of Cu2+ ions was spontaneous, feasible, endothermic and physical in nature. Regeneration studies also revealed that GFLE could be consistently reused up to 3 cycles.

2020 ◽  
Vol 15 (2) ◽  
pp. 460-471
Author(s):  
T. Unugul ◽  
F. U. Nigiz

Abstract In this study; acid treated carbonized mandarin peel (CMP) adsorbent was prepared and the adsorption behaviour of the adsorbent for copper removal was investigated. In the adsorption studies the effects of initial metal concentration, solution pH, adsorbent dosage and contact time on the removal were investigated. As a result; the highest removal of 100% was achieved when the copper concentration in water was 5 mg/L and the adsorbent dosage was 3.75 g/L at a solution pH of 7. Isotherm studies were also done and the appropriate isotherm was obtained as the Freundlich isotherm. According to the kinetic studies, the copper adsorption onto CMP adsorbent was adopted to the pseudo-second-order adsorption kinetic. After HCl regeneration, the adsorbent maintained 94% of its activity.


2016 ◽  
Vol 74 (11) ◽  
pp. 2560-2568 ◽  
Author(s):  
Qiulai He ◽  
Hongyu Wang ◽  
Jing Zhang ◽  
Zhuocheng Zou ◽  
Jun Zhou ◽  
...  

The adsorption of methylene blue (MB) by low cost biomass lotus seedpod (LSP) was optimized by a central composite design combined with response surface methodology in aqueous solution. Solution pH, initial dye concentration and adsorbent dosage were studied as independent variables at five levels each, respectively. Analysis of variance suggested the validity of the regression model. LSP was characterized by Fourier transform infrared spectra and energy dispersive spectroscopy. The kinetics revealed that the adsorption behavior followed the pseudo-second-order model. Langmuir and Freundlich isotherm models were used to evaluate the adsorption, and the experimental data were better fitted by the Langmuir isotherm than the Freundlich isotherm. The maximum monolayer adsorption capacity of the LSP was 157.98 mg g−1 at 30 °C for MB adsorption. In addition, 0.2 M HCl solution could be used for reusability of LSP via desorption tests. LSP was proven to be an available and effective biosorbent for MB removal from aqueous solution.


Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 63
Author(s):  
Maria Harja ◽  
Gabriela Buema ◽  
Nicoleta Lupu ◽  
Horia Chiriac ◽  
Dumitru Daniel Herea ◽  
...  

Fly ash/magnetite material was used for the adsorption of copper ions from synthetic wastewater. The obtained material was characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area, and vibrating sample magnetometer (VSM). Batch adsorption experiments were employed in order to investigate the effects of adsorbent dose, initial Cu (II) concentration and contact time over adsorption efficiency. The experimental isotherms were modeled using Langmuir (four types of its linearization), Freundlich, Temkin, and Harkins–Jura isotherm models. The fits of the results are estimated according to the Langmuir isotherm, with a maximum adsorption capacity of 17.39 mg/g. The pseudo-second-order model was able to describe kinetic results. The data obtained throughout the study prove that this novel material represents a potential low-cost adsorbent for copper adsorption with improved adsorption capacity and magnetic separation capability compared with raw fly ash.


Author(s):  
Xiaochun Yin ◽  
Nadi Zhang ◽  
Meixia Du ◽  
Hai Zhu ◽  
Ting Ke

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.


Author(s):  
N. O. Ilelaboye ◽  
A. A. Oderinde

Increased anthropogenic activities have led to serious environmental problems due to pollution caused by toxic materials such as heavy metals whose levels are rising in the environment. The inefficiency and high cost of conventional methods of waste treatment have prompted the investigation of environmentally friendly and cheaper methods of treatment using natural products. In this study, G. arborea leaves powder was investigated with a view of using it as cheap material for the biosorption of Pb2+ and Cd2+   from wastewater. The effects of operational parameters like pH, biosorbent dose [g/L], initial metal ions concentration [mg/L], contact time [minutes] and stirring speed [rpm] on the biosorption efficiency [%] were determined. The optimum solution pH for Pb2+ and Cd2+adsorption was 5.0 and peak adsorption of 91.33% and 82.53% for Pb2+ and Cd2+, respectively. 5 g/L Melina leaves were enough to achieve peak removal of both metal ions. The removal of the metal ions was comparatively quick, and stability was achieved after 30 minutes. The optimum stirring speed was 250 rpm for both metal ions. The uptake efficiency of the biosorbent was determined by Langmuir and Freundlich isotherm models. The value of Langmuir isotherm separation parameter [RL] of Pb2+ ion [0.0446 - 0.78125] and Cd2+ [0.1005- 0.9482] were within range of 0 -1 indicating favorable biosorption for both metal ions. The degree of non-linearity [n] values between Pb2+ [12.79] and Cd2+ [11.79] solution concentration and biosorption in Freundlich equation were greater than 1, indicating physical biosorption of Pb2+ and Cd2+ on to G. arborea leaves. G. arborea can serve as efficient biosorbent not only for Pb2+ and Cd2+ ions but also for other heavy metal ions in a wastewater stream


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Dong-Hui Cheng ◽  
Sheng-Ke Yang ◽  
Yue Zhao ◽  
Jing Chen

Adsorption behaviors of oxytetracycline onto sediment in the Weihe River were described. The impact factors in the processes of adsorption, such as contact time, solution pH, temperature, and ionic strength, were determined by experiments. The experimental results were analyzed by kinetic and isotherm models. The adsorption kinetics was found to follow a pseudo-first-order model. The equilibrium adsorption data fitted well with the Langmuir and Freundlich isotherm models. However, the Langmuir isotherm was more suitable to describe the adsorption. Thermodynamics parameters such as Gibbs-free energy change (ΔG°), enthalpy change (ΔH°), and entropy change (ΔS°) were calculated. Results showed that the adsorption was feasible, spontaneous, entropy increasing, and endothermic in nature, which reached equilibrium in about 24 hours. The adsorption capacity did not cause obvious change at solution pH 4.0–7.0, and both decreased in solution pH 7.0–10.0 and 4.0–2.0. The presence of electrolytes such as NaCl in aqueous solution had a significant negative effect on the adsorption. The mechanisms controlling the adsorption were supposed to be chemisorption.


2018 ◽  
Vol 78 (4) ◽  
pp. 827-836 ◽  
Author(s):  
Aysun Bulut ◽  
Sabriye Yusan ◽  
Sule Aytas ◽  
Senol Sert

Abstract This study aimed to investigate and explore the possibility of using ground sea shell powder (Donax trunculus) (SSP) for sorption of Sr(II) ions from aqueous solutions. The maximum removal of Sr(II) removal in SSP was 60% at initial Sr(II) concentration of 25 mg/L, at pH 6.0, contact time 120 min, temperature 25 °C and volume/mass ratio equivalent to 500. Sorption data were interpreted considering the adsorption isotherms and thermodynamic parameters calculated. The maximum Sr(II) adsorption on SSP was 25.45 mg/g at pH 6.0. Freundlich isotherm and Dubinin–Radushkevich models were seen to be more compatible with the sorption equilibrium. The nature of the process was spontaneous and exothermic. The results suggest that SSP could be used as an efficient and cost-effective adsorbent to remove strontium ion.


Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 626 ◽  
Author(s):  
Salah ◽  
Gaber ◽  
Kandil

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.


2019 ◽  
Vol 107 (5) ◽  
pp. 377-386 ◽  
Author(s):  
Cansu Endes Yılmaz ◽  
Mahmoud A.A. Aslani ◽  
Ceren Kütahyalı Aslani

Abstract Adsorption of thorium onto nitric acid modified multi-walled carbon nanotubes was investigated by central composite design as a function of contact time, pH, initial thorium concentration and temperature. The results showed that optimum uptake capacity was 65.75±2.23 mg·g−1 with respect to pH=4, initial thorium concentration of 100 mg·L−1, 25 °C and 15 min contact time. Thermodynamic parameters [standard enthalpy (ΔH0), entropy (ΔS0), and free energy (ΔG0)] were calculated, and the results indicated that adsorption was endothermic. Langmuir, Freundlich and Dubinin-Radushkevich isotherms have been investigated in order to characterize the adsorption process in the range of 25–100 mg·L−1 initial thorium concentration. The Freundlich isotherm is the best suited as a model because it has the highest correlation coefficient (R2=0.9485). The pseudo-second order kinetics well defined the adsorption process.


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