scholarly journals ADSORPTION CHARACTERISTICS OF ZIZYPHUS JUJUBA SEED SHELL ACTIVATED NANO POROUS CARBON FOR REMOVING COPPER (II) IONS FROM WASTEWATER

2016 ◽  
Vol 4 (12) ◽  
pp. 226-241
Author(s):  
K Veeravelan ◽  
S Arivoli ◽  
V Marimuthu

In the present study, adsorption of copper (II) ions from aqueous solution by Activated Zizyphus Jujuba shell Nano Carbon was investigated under batch mode. The influence of solution pH, sorbent dose, copper concentration, contact time and temperature was studied. The copper adsorption was favored with maximum adsorption at pH 6.5. Sorption equilibrium time was observed in 60 min. The equilibrium adsorption data were correlated with Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Hurkins-Jura, Halsay, Radlich-Peterson, Jovanovic and BET isotherm models. The kinetics of the adsorption process was tested by pseudo-first-order, pseudo-second order, Elovich and Intra-particle diffusion models. It was shown that adsorption of copper could be described by the pseudo-second order kinetic model. Thermodynamic parameters such as Gibbs free energy (ΔG0), the enthalpy (ΔH0) and the entropy change of sorption (ΔS0) have also been evaluated and it has been found that the adsorption process was spontaneous, feasible and endothermic in nature. The results indicated that Activated Zizyphus Jujuba shell Nano Carbon can be used as an effective and low-cost adsorbent to remove copper (II) from aqueous solution.

2019 ◽  
Vol 9 (21) ◽  
pp. 4486 ◽  
Author(s):  
Candelaria Tejada-Tovar ◽  
Angel Darío Gonzalez-Delgado ◽  
Angel Villabona-Ortiz

The removal of water pollutants has been widely addressed for the conservation of the environment, and novel materials are being developed as adsorbent to address this issue. In this work, different residual biomasses were employed to prepare biosorbents applied to lead (Pb(II)) ion uptake. The choice of cassava peels (CP), banana peels (BP), yam peels (YP), and oil palm bagasse (OPB) was made due to the availability of such biomasses in the Department of Bolivar (Colombia), derived from agro-industrial activities. The materials were characterized by ultimate and proximate analysis, Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller analysis (BET), Scanning Electron Microscopy (SEM), and Energy Dispersive X-Ray Spectroscopy (EDS) in order to determine the physicochemical properties of bioadsorbents. The adsorption tests were carried out in batch mode, keeping the initial metal concentration at 100 ppm, temperature at 30 °C, particle size at 1 mm, and solution pH at 6. The experimental results were adjusted to kinetic and isotherm models to determine the adsorption mechanism. The remaining concentration of Pb(II) in solution was measured by atomic absorption at 217 nm. The functional groups identified in FTIR spectra are characteristic of lignocellulosic materials. A high surface area was found for all biomaterials with the exception of yam peels. A low pore volume and size, related to the mesoporous structure of these materials, make these bioadsorbents a suitable alternative for liquid phase adsorption, since they facilitate the diffusion of Pb(II) ions onto the adsorbent structure. Both FTIR and EDS techniques confirmed ion precipitation onto adsorbent materials after the adsorption process. The adsorption tests reported efficiency values above 80% for YP, BP, and CP, indicating a good uptake of Pb(II) ions from aqueous solution. The results reported that Freundlich isotherm and pseudo-second order best fit experimental data, suggesting that the adsorption process is governed by chemical reactions and multilayer uptake. The future prospective of this work lies in the identification of alternatives to reuse Pb(II)-contaminated biomasses after heavy metal adsorption, such as material immobilization.


Author(s):  
Armin Geroeeyan ◽  
Ali Niazi ◽  
Elaheh Konoz

Abstract In the present research, the removal of Basic Orange 2 (BO2) dye using alkaline-modified clay nanoparticles was studied. To characterize the adsorbent, XRD, FTIR, FESEM, EDX, BET and BJH analyses were performed. The effect of the variables influencing the dye adsorption process such as adsorbent dose, contact time, pH, stirring rate, temperature, and initial dye concentration was investigated. Furthermore, the high efficiency of Ni2+ removal indicated that it is possible to remove both dye and metal cation under the same optimum conditions. The experimental data were analyzed by Langmuir and Freundlich isotherm models. Fitting the experimental data to Langmuir isotherm indicated that the monolayer adsorption of dye occurred at homogeneous sites. Experimental data were also analyzed with pseudo-first-order, pseudo-second-order, and intra-particle diffusion kinetic equations for kinetic modeling of the dye removal process. The adsorption results indicated that the process follows a pseudo-second-order kinetic model. The thermodynamic parameters of the dye adsorption process such as enthalpy, entropy, and Gibbs free energy changes were calculated and revealed that the adsorption process was spontaneous and endothermic in nature. The results presented the high potential of the modified nanoclay as a cost-effective adsorbent for the removal of BO2 dye and Ni2+ from aqueous medium.


2021 ◽  
pp. 1-12
Author(s):  
Raafia Najam ◽  
Syed Muzaffar Ali Andrabi

Sawdust of willow has been investigated as an adsorbent for the removal of Ni(II), and Cd(II) ions from aqueous solution. Since willow tree is widely grown in almost all parts of Kashmir, it can be a common most easily available, sustainable, low cost adsorbent for the treatment of wastewaters in this part of the world where growing industrialization is affecting water quality like elsewhere in the world. Therefore, it is worthwhile to investigate the potential of sawdust of willow tree as an adsorbent for the removal of Ni(II) and Cd(II) ions from aqueous solution as a first step. Batch experiments were conducted to study the effect of some parameters such as contact time, initial concentration of metal ions, solution pH and temperature. Langmuir and Freundlich models were employed for the mechanistic analysis of experimental data obtained. Results reveal that in our system adsorption follows the Langmuir isotherm. The maximum adsorption capacity of Ni(II) and Cd(II) were found to be 7.98 and 7.11 mg/g respectively at optimum conditions. The pseudo-first-order and pseudo-second-order models were employed for kinetic analysis of adsorption process. The adsorption process follows pseudo-second-order kinetics. The efficacy of the adsorbent in the treatment of effluent from fertilizer factory has been investigated and the results have been found encouraging.


2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Ying-Xia Ma ◽  
Yong-Xin Ruan ◽  
Dan Xing ◽  
Xue-Yan Du ◽  
Pei-Qing La

Ethylenediamine functionalized magnetic expanded graphite decorated with Fe3O4 nanoparticles (MEG-NH2) was fabricated by one-pot solvothermal method. The as-prepared MEG-NH2 nanohybrids were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and Zeta potential analyzer. The effects of Fe3O4 content in MEG-NH2 nanohybrids, pH, initial concentration, contact time, and dosage on adsorption properties of the MEG-NH2 nanohybrids for Ag(I) from aqueous solution were investigated by batch experiments. The pseudo-first-order and the pseudo-second-order kinetic models were utilized to study adsorption kinetics. The experimental data was also analyzed with Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models. The results show that Ag(I) was reduced to silver in the process of the adsorption by MEG-NH2 nanohybrids; the experimental data was better fitted to pseudo-second-order model and Langmuir isotherm model which revealed that the adsorption process was a chemical adsorption by the formation of silver on the surface of MEG-NH2 nanohybrids.


2015 ◽  
Vol 73 (2) ◽  
pp. 423-436 ◽  
Author(s):  
Çisem Kırbıyık ◽  
Ayşe Eren Pütün ◽  
Ersan Pütün

In this study, Fe(III) and Cr(III) metal ion adsorption processes were carried out with three adsorbents in batch experiments and their adsorption performance was compared. These adsorbents were sesame stalk without pretreatment, bio-char derived from thermal decomposition of biomass, and activated carbon which was obtained from chemical activation of biomass. Scanning electron microscopy and Fourier transform–infrared techniques were used for characterization of adsorbents. The optimum conditions for the adsorption process were obtained by observing the influences of solution pH, adsorbent dosage, initial solution concentration, contact time and temperature. The optimum adsorption efficiencies were determined at pH 2.8 and pH 4.0 for Fe(III) and Cr(III) metal ion solutions, respectively. The experimental data were modelled by different isotherm models and the equilibriums were well described by the Langmuir adsorption isotherm model. The pseudo-first-order, pseudo-second-order kinetic, intra-particle diffusion and Elovich models were applied to analyze the kinetic data and to evaluate rate constants. The pseudo-second-order kinetic model gave a better fit than the others. The thermodynamic parameters, such as Gibbs free energy change ΔG°, standard enthalpy change ΔH° and standard entropy change ΔS° were evaluated. The thermodynamic study showed the adsorption was a spontaneous endothermic process.


2015 ◽  
Vol 72 (9) ◽  
pp. 1505-1515 ◽  
Author(s):  
H. Asnaoui ◽  
A. Laaziri ◽  
M. Khalis

Batch experiments were conducted to study the adsorption of hazardous cadmium onto low-cost algae biomass in aqueous solution with respect to concentration of adsorbate, adsorbent dosage, contact time, solution pH and temperature. Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were determined. The activation energy of adsorption was also evaluated for the adsorption of cadmium onto Ulva lactuca biomass. Experimental data were tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of Cd(II) followed well pseudo-second-order kinetics. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the metal ions by Ulva lactuca biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The biosorption capacity of Ulva lactuca biomass for cadmium was found to be 3.02 mg/g at pH 5.60 min equilibrium time and 20 °C. The mean free energy which was calculated was 6.24 kJ/mol for Cd(II) biosorption, which shows that the adsorption is physical. The calculated thermodynamic parameters (ΔG0, ΔH0 and ΔS0) showed that the biosorption of Cd(II) onto Ulva lactuca biomass was feasible, spontaneous and exothermic under examined conditions. The results indicate that algae Ulva lactuca could be employed as a low-cost material for the removal of metal ions from aqueous solution.


2021 ◽  
Vol 11 (7) ◽  
Author(s):  
Bilsen Tural ◽  
Erdal Ertaş ◽  
Mehmet Güzel ◽  
Servet Tural

AbstractIn this study, pumice from different regions of Turkey (Diyarbakir, Southeast Turkey and Bitlis, East Turkey) has been supplied and used as supporting material for nanoscale zero-valent iron (nFe0). Native Bitlis pumice (NBP)-supported nanoscale zero-valent iron (BP-nFe0) and native Diyarbakir pumice (NDP)-supported nanoscale zero-value iron (DP-nFe0) were synthesized under the same conditions. Native pumice (NDP, NBP) and pumice-supported nFe0 (DP-nFe0 and BP-nFe0) adsorbents were morphologically and structurally characterized by SEM, EDX, XRF and BET. When using NBP as support material, the iron content of the BP-nFe0 increased 1.9-fold from 1.99 to 3.83%. However, iron content of NDP (2.08%) increased approximately 29 times after it is used as a support material in synthesis of DP-nFe0 (60%). The removal potential of native pumice (NBP and NDP) and iron-modified pumice (BP-nFe0 and DP-nFe0) samples was investigated to remove Cr(VI) ions. The parameters of solution pH, initial metal concentration, contact time and the amount of adsorbent in the removal of chromium (VI) ions were investigated. Langmuir, Freundlich, Temkin, Dubinin–Radushkevich and Jovanovic isotherm models were used to evaluate the adsorption equilibrium data. The equilibrium adsorption was found so as to be well described by the Langmuir isotherm model for all the adsorbents studied. The maximum adsorption capacity of Cr(VI) ions for NDP, NBP, DP-nFe0 and BP-nFe0 was 10.82, 14.30, 161.29 and 17.39 mg/g, respectively. The rate of Cr(VI) removal was subjected to kinetic analysis using pseudo-first-order, pseudo-second-order, intraparticle diffusion and Elovich models. Kinetic studies suggest that adsorption of NDP, NBP, DP-nFe0 and BP-nFe0 described more favorably by the pseudo-second-order kinetic model. The results showed that NDP is a much better support material for nFe0 when compared to NBP.


2016 ◽  
Vol 7 (3) ◽  
pp. 307-318 ◽  
Author(s):  
F. Z. Mahjoubi ◽  
A. Khalidi ◽  
O. Cherkaoui ◽  
R. Elmoubarki ◽  
M. Abdennouri ◽  
...  

This work involved the preparation, characterization and dyes removal ability of Zn-Al, Mg-Al and Ni-Al layered double hydroxide (LDH) minerals intercalated by chloride ions. The materials were synthetized by the co-precipitation method. X-ray diffraction, Fourier transform infrared, thermogravimetric-differential thermal analysis and transmission electron microscopy characterization exhibited a typical hydrotalcite structure for all the samples. Adsorption experiments for methyl orange were performed in terms of solution pH, contact time and initial dye concentration. Experimental results indicate that the capacity of dye uptake augmented rapidly within the first 60 min and then stayed practically the same regardless of the concentration. Maximum adsorption occurred with acidic pH medium. Kinetic data were studied using pseudo-first-order and pseudo-second-order kinetic models. Suitable correlation was acquired with the pseudo-second-order kinetic model. Equilibrium data were fitted to Langmuir and Freundlich isotherm models. The maximum Langmuir monolayer adsorption capacities were 2,758, 1,622 and 800 mg/g, respectively, for Zn-Al-Cl, Mg-Al-Cl and Ni-Al-Cl. The materials were later examined for the elimination of color and chemical oxygen demand (COD) from a real textile effluent wastewater. The results indicated that the suitable conditions for color and COD removal were acquired at pH of 5. The maximum COD removal efficiency from the effluent was noted as 92.84% for Zn-Al-Cl LDH.


2010 ◽  
Vol 62 (10) ◽  
pp. 2435-2441 ◽  
Author(s):  
R. Malarvizhi ◽  
Y. Venkateswarlu ◽  
V. Ravi babu ◽  
S. Syghana Begum

Environmental contamination by toxic heavy metals is a significant universal problem. The main objective of the study is to use a biodegradable materials like Cyperus pangorei and Chitosan as a composite biosorbent for the removal of Cr(VI) from water. The newly prepared biosorbent is characterized and the capacity of Cr(VI) removal of the biosorbent is carried out systematically by batch mode operations. The adsorption capacity of the biosorbent is examined by changing the parameters like biosorbent dose, varying the initial contact time, varying initial concentration of metal ion and pH of the metal ion solution to know the actual mechanism taking place during the initial sorption process. The experimental data obtained were fitted with the Freundlich, Langmuir and Redlich–Peterson isotherm models and the pseudo first order and the pseudo second order kinetic models. Equilibrium data were fitted very well to the Langmuir Isotherm model and pseudo second order kinetic model. Desorption of the metal ion is also carried out using different concentration of NaOH.


Author(s):  
Khawla Ben Jeddou ◽  
Fatma Bouaziz ◽  
Fadia Ben Taheur ◽  
Oumèma Nouri-Ellouz ◽  
Raoudha Ellouz-Ghorbel ◽  
...  

Abstract Adsorption of direct red 80 (DR 80) and methylene blue (MB) from aqueous solutions on potato peels (PP) has been compared. The use of peels in decontamination technology is very promising given the near zero-cost for the synthesis of those adsorbents. The selected potato peels were first analyzed by scanning using electron microscopy (SEM) and Fourier transforms infra red spectroscopy (FTIR). Then the adsorption behavior was studied in a batch system. The adsorption process is affected by various parameters such as the solution pH (2–11), the initial concentration of the dye (20, 50, 100, 150 and 200 mg L−1), the adsorbent dose (0.1%–3%), the temperature (303.16 K, 313.16 K, and 323.16 K), agitation (up to 250 rpm), as well as the contact time. Adsorption isotherms of the studied dye on the adsorbent were determined and compared with the Langmiur, Freundlich and Temkin adsorption models. The results show that the data was most similar to the Freundlich isotherm (R2 = 0.99). The maximum adsorption capacities (Qmax) of MB and DR 80 by the PP at temperatures 303.16 K, 313.16 K and 323.16 K were found to be approximately 97.08 mg g−1; 45.87 mg g−1; 61.35 mg g−1 and 27.778 mg g−1; 45.45 mg g−1; and 32.258 mg g−1. The kinetic data was compared to the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. This revealed that adsorption of methylene blue onto PP abided mostly to the pseudo-second-order kinetic model. Calculations of various thermodynamic parameters such as enthalpy change (ΔH), entropy change (ΔS), and free energy change (ΔG) display the endothermic and spontaneous nature of the adsorption process.


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