scholarly journals Removal of Cr(VI) and Cu(II) Ions from Aqueous Solution by Carbon Prepared from Henna Leaves

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
T. Shanthi ◽  
V. M. Selvarajan
Keyword(s):  
Contact Time ◽  
Metal Ion ◽  
Metal Removal ◽  
Ph Value ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Lawsonia Inermis ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Adsorbent Dosage

Carbon prepared from leaves of henna (Lawsonia inermis) was used to study the adsorption of Cr(VI) and Cu(II) ions from their aqueous solutions. The experimental conditions which include pH, contact time, initial concentration, and adsorbent dosage on the metal removal were investigated. The capacity of adsorption depends on pH value; it increases with an increase in pH value from 1 to 7 and then decreases. The highest percentage of metal removal was achieved in the adsorbent dosage of 0.7 g and at an initial concentration of 100 ppm metal ion. The adsorption isotherm studies revealed that data was confirmed with both the Langmuir and Freundlich isotherm models. The removal percentage was found to be higher for Cu(II) when compared with Cr(VI). The potential of carbon prepared from henna leaves for the removal of these two solutions containing heavy metals was substantiated.

Nanoparticle Fe3O4 magnetized activated carbon from Armeniaca sibirica shell for the adsorption of Hg(II) ions

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 6100-6120
Author(s):  
Yinan Hao ◽  
Yanfei Pan ◽  
Qingwei Du ◽  
Xudong Li ◽  
Ximing Wang
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Entropy Change ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Initial Concentration

Armeniaca sibirica shell activated carbon (ASSAC) magnetized by nanoparticle Fe3O4 prepared from Armeniaca sibirica shell was investigated to determine its adsorption for Hg2+ from wastewater. Fe3O4/ASSAC was characterized using XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and BET (Brunauer–Emmett–Teller). Optimum adsorption parameters were determined based on the initial concentration of Hg2+, reaction time, reaction temperature, and pH value in adsorption studies. The experiment results demonstrated that the specific surface area of ASSAC decreased after magnetization; however the adsorption capacity and removal rate of Hg2+ increased 0.656 mg/g and 0.630%, respectively. When the initial concentration of Hg2+ solution was 250 mg/L and the pH value was 2, the adsorption time was 180 min and the temperature was 30 °C, and with the Fe3O4/ASSAC at 0.05 g, the adsorption reaching 97.1 mg/g, and the removal efficiency was 99.6%. The adsorption capacity of Fe3O4/ASSAC to Hg2+ was in accord with Freundlich isotherm models, and a pseudo-second-order kinetic equation was used to fit the adsorption best. The Gibbs free energy ΔGo < 0，enthalpy change ΔHo < 0, and entropy change ΔSo < 0 which manifested the adsorption was a spontaneous and exothermic process.

scholarly journals Optimization, equilibrium and kinetic studies of Zn2+ and Ni2+ adsorption from aqueous solutions using composite adsorbent

2018 ◽  
Vol 67 (3) ◽  
pp. 279-290 ◽  
Author(s):  
Haider M. Zwain ◽  
Mohammadtaghi Vakili ◽  
Irvan Dahlan
Keyword(s):  
Contact Time ◽  
Coal Fly Ash ◽  
Sol Gel ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Isotherm Models ◽  
Experimental Conditions ◽  
Palm Oil Fuel Ash ◽  
Composite Adsorbent ◽  
Oil Fuel

Abstract A novel RHA/PFA/CFA composite adsorbent was synthesized from rice husk ash (RHA), palm oil fuel ash (PFA), and coal fly ash (CFA) by modified sol-gel method. Effect of different parameters such as adsorbent dosage, contact time, and pH were studied using batch experiment to optimize the maximum zinc (Zn2+) and nickel (Ni2) adsorption conditions. Results showed that the maximum adsorption condition occurred at adsorbent amount of 10 g/L, contact time of 60 min, and pH 7. At this condition, the removal efficiencies were 81% and 61% for Zn2+ and Ni2+, in which the adsorption capacities (qmax) were 21.74 mg/g and 17.85 mg/g, respectively. Adsorption behavior of RHA/PFA/CFA composite adsorbent was studied through the various isotherm models at different adsorbent amounts. The results indicated that the Freundlich isotherm model gave an excellent agreement with the experimental conditions. Based on the results obtained from the kinetic studies, pseudo-second-order was suitable for the adsorption of Ni2+ and Zn2+, compared to the pseudo-first-order model. The results presented in this study showed that RHA/PFA/CFA composite adsorbent successfully adsorbed Zn2+ and Ni2.

scholarly journals Adsorption of Nickel and Chromium From Aqueous Solutions Using Copper Oxide Nanoparticles: Adsorption Isotherms, Kinetic Modeling, and Thermodynamic Studies

2019 ◽  
Vol 6 (2) ◽  
pp. 66-74 ◽  
Author(s):  
Raziyeh Hosseini ◽  
Mohammad Hossein Sayadi ◽  
Hossein Shekari
Keyword(s):  
Aqueous Solutions ◽  
Copper Oxide ◽  
Removal Efficiency ◽  
Contact Time ◽  
Removal Rate ◽  
Copper Oxide Nanoparticles ◽  
Isotherm Models ◽  
Oxide Nanoparticles ◽  
Initial Concentration ◽  
Adsorbent Dosage

The research was conducted with an aim to assess the efficiency of copper oxide nanoparticles as an adsorbent to remove Ni and Cr. The effect of pH, adsorbent dosage, contact time, initial concentration of metals (Ni and Cr) on the adsorption rate was evaluated and removal of these elements from aqueous solutions was measured using Atomic Absorption Spectrum System (Conter AA700). Moreover, the kinetic and isotherm besides thermodynamic adsorption models were assessed. The highest Ni and Cr removal rate occurred at an optimal pH of 7, and an initial concentration of 30 mg/L, a time period of 30 minutes, and 1 g/L of copper oxide nanoparticles. In fact, with the increase of adsorbent dosage and contact time, the removal efficiency increased and with initial concentration increase of Ni and Cr ions, the removal efficiency reduced. The correlation coefficient of isotherm models viz. Langmuir, Freundlich, Temkin, Redlich-Peterson, and Koble-Corrigan showed that Ni and Cr adsorption via copper oxide nanoparticles better follows the Langmuir model in relation to other models. The results showed that kinetic adsorption of Ni and Cr via copper oxide nanoparticles follows the second order pseudo model with correlation coefficients above 0.99. In addition, the achieved thermodynamic constants revealed that the adsorption process of metals (i.e., Ni and Cr) via copper oxide nanoparticles was endothermic and spontaneous and the reaction enthalpy values for these metals were 17.727 and 11.862 kJ/mol, respectively. In conclusion, copper oxide nanoparticles can be used as effective and environmentally compatible adsorbents to remove Ni and Cr ions from the aqueous solutions

scholarly journals Biosorption of Cr(III) from aqueous solution using an agricultural by-product jute stick powder: Equilibrium and kinetic studies

2018 ◽  
Vol 9 (3) ◽  
pp. 202-212 ◽  
Author(s):  
Mohammad Nasir Uddin ◽  
Jahangir Alam ◽  
Syeda Rahimon Naher
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Metal Ion ◽  
Water Solution ◽  
Low Cost ◽  
Isotherm Models ◽  
Infrared Spectrometry ◽  
Order Kinetic ◽  
Adsorption Model ◽  
Experimental Conditions

The adsorption capacity of chromium(III) from synthetic waste water solution by a low cost biomaterial, Jute Stick Powder (JSP)was examined. A series of batch experiments were conducted at different pH values, adsorbent dosage and initial chromium concentration to investigate the effects of these experimental conditions. To analyze the metal adsorption on to the JSP, most common adsorption isotherm models were applied. To study the reaction rate, the kinetic and diffusion models were also applied. The morphological structure and variation of functional groups in the JSP before and after adsorption was examined by scanning electron microscope (SEM) and Fourier transform infrared spectrometry (FT-IR). Maximum chromium removal capacities of JSP was 84.34%with corresponding equilibrium uptake 8.4 mg/g from 50 mg/L of synthetic metal solution in 60 minutes of contact time at pH = 6.0 and 28 °C with continuous stirring at 180 rpm. The percent sorption of the biomass decreased with increasing concentration of metal ion but increased with decreasing pH, increasing contact time and adsorbent doses. Data for this study indicated a good correspondence with both isotherms of Langmuir and Freundlich isotherm. The analysis of kinetic indicated that Chromium was consistent with the second-order kinetic adsorption model. The rate of removal of Cr(III) ions from aqueous solution by JSP was found rapid initially within 5-30 minutes and reached in equilibrium in about 40 minutes. The investigation revealed that JSP, a low cost agricultural byproduct, was a potential adsorbent for removal of heavy metal ions from aqueous solution.

Adsorption of copper and lead in single and binary metal system onto Fumaria indica biomass

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Metal Ion ◽  
Metal Removal ◽  
Aqueous Media ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Metal System ◽  
Lead Adsorption ◽  
Binary Metal ◽  
Binary Metal System ◽  
Adsorption Data

Among heavy metals, lead and copper pose a significant threat to the due to their toxicity, incremental accumulation in the food chain and persistence in the ecosystem. Lead and copper are introduced into water from various industries and other human activities. Present study was aimed to remove lead and copper from aqueous media using Fumaria indica biomass as a function of metal ions initial concentration. Both metal removal was investigated in single and binary system. For comparison isotherm models i.e., Langmuir and Freundlich were applied on experimental adsorption data. Results showed that the copper behavior was different in single and binary metal system, whereas lead adsorption remained the same in both single and binary metal systems. The Freundlich isotherm model fitted well to the adsorption data of both single and binary metal system. The thermodynamic parameters i.e., ΔG0, was measured to get insight into adsorption phenomenon and negative value of ΔG0 suggest that the adsorption process was spontaneous in nature. Results showed that in multi-metal system the adsorption of specific metal ion may change and during metal adsorption from industrial wastewater this effect must be taken in account before generalization of results.

scholarly journals ADSORPTION OF FLUORIDE USING SIO2 NANOPARTICLES AS ADSORBENT

2020 ◽  
Vol 2 (2) ◽  
pp. 1-9
Author(s):  
Davoud Balarak ◽  
Yousef Mahdavi ◽  
Ali Joghatayi
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Sio2 Nanoparticles ◽  
Second Order ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Initial Concentration ◽  
High Doses

Presence of Fluoride in water is safe and effective when used as directed, but it can be harmful at high doses. In the present paper SiO2 nanoparticles as a adsorbent is used for removal of fluoride from aqueous solution. The effect of various operating parameters such as initial concentration of F-, Contact time, adsorbent dosage and pH were investigated. Equilibrium isotherms were used to identify the possible mechanism of the adsorption process. Maximum adsorption capacity of the SiO2 nanoparticles was 49.95 mg/g at PH=6, contact time 20 min, initial concentration of 25 mg/L, and 25±2 ◦C temperatures, when 99.4% of Fwere removed. The adsorption equilibriums were analyzed by Langmuir and Freundlich isotherm models. It was found that the data fitted to Langmuir (R2=0.992) better than Freundlich (R2=0.943) model. Kinetic analyses were conducted using pseudo first-and second-order models. The regression results showed that the adsorption kinetics was more accurately represented by a pseudo second-order model. These results indicate that SiO2 nanoparticles can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution.

scholarly journals Removal of Pb(II) from Aqueous Solution by Ceramsite Prepared from Isfahan Bentonite and γ-Alumina

2021 ◽  
Vol 15 (2) ◽  
pp. 263-273
Author(s):  
Iman Mobasherpour ◽  
◽  
Masomeh Javaherai ◽  
Esmail Salahi ◽  
Mohsen Ebrahimi ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
The Novel ◽  
Absorption Process ◽  
Initial Concentration ◽  
Adsorbent Dosage ◽  
Adsorption Data ◽  
Ft Ir ◽  
Central Composite

Removal of lead from aqueous solutions was studied using nanocomposite absorbent of bentonite/-alumina. The novel absorbent was characterized using XRD, FT-IR and SEM-EDX. Absorption process optimization using response surface methodology (RSM) and experimental design was performed with central composite design technique. The effects of Pb(II) initial concentration, adsorbent dosage, and composite percentage on Pb(II) removal percentage and adsorption capacity were examined. The adsorption capacity of 166.559 mg/g and removal % of 82.9887 with desirability equal to 0.763 were obtained for optimal initial concentration of 200 mg•l-1, adsorbent dosage of 0.5 mg•l-1, and composite percentage of 7.08 % determined using RSM design. The equilibrium adsorption data were investigated by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. It was found that Freundlich isotherm model fits better compared with other models.

scholarly journals Adsorption of cadmium and copper onto natural clay: isotherm, kinetic and thermodynamic studies

2018 ◽  
Vol 20 (2) ◽  
pp. 198-207 ◽  
Keyword(s):  
Mass Transfer ◽  
Metal Ions ◽  
Contact Time ◽  
Freundlich Isotherm ◽  
Adsorption Rate ◽  
Isotherm Models ◽  
Experimental Conditions ◽  
Adsorption Data ◽  
Removal Of Heavy Metals ◽  
Heavy Metals Ions

Clay of the Middle Atlas Mountains region, Morocco, was used to investigate the removal of heavy metals ions (Cadmium and Copper) from aqueous solutions with respect to several experimental conditions including pH, contact time, initial solute concentrations, temperature and ionic strength. Kinetic study revealed that metal ions uptake was fast with 90% or more of the adsorption occurring within first 30 min of contact time. Adsorption rate increased with the increasing initial metal ions concentrations and the sorption rate was well fitted by the pseudo-second-order rate model. The data according to mass transfer and intraparticle diffusion models confirmed diffusion of solutes inside the clay particles as the rate-controlling step and more important for the adsorption rate than the external mass transfer. The suitability of the adsorbent was tested by fitting the adsorption data with Langmuir and Freundlich isotherm models. Equilibrium and kinetic adsorption data showed that clay displays a high selectivity with an affinity order of Cd > Cu. Thermodynamic parameters including the Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) changes indicated that the present adsorption process was feasible and endothermic in the temperature range of 25–45 °C.

scholarly journals Barium/Cobalt@Polyethylene Glycol Nanocomposites for Dye Removal from Aqueous Solutions

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1161
Author(s):  
Somayeh Rahdar ◽  
Abbas Rahdar ◽  
Mostafa Sattari ◽  
Laleh Divband Hafshejani ◽  
Athanasia K. Tolkou ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Contact Time ◽  
Skin Diseases ◽  
Freundlich Isotherm ◽  
Order Kinetic ◽  
Initial Concentration ◽  
Adsorbent Dosage ◽  
Order Kinetic Model

Dyes are known as one of the most dangerous industrial pollutants which can cause skin diseases, allergy, and provoke cancer and mutation in humans. Therefore, one of the important environmental issues is the effective removal of dyes from industrial wastewater. In the current work, BaFe12O19/CoFe2O4@polyethylene glycol (abbreviated as BFO/CFO@PEG) nanocomposite was synthesized and evaluated regarding its capacity for adsorptive removal of a model dye Acid Blue 92 (denoted as AB92) from aqueous solutions. The characteristics of the prepared nanocomposite was determined by tests such as X-ray diffraction (XRD), scanning electron microscope (SEM), vibration sample magnetization (VSM), and Fourier transform infrared spectroscopy (FTIR). The effects of conditional parameters including pH (2–12), initial concentration of dye (20–100 mg/L), adsorbent dosage (0.02–0.1 g/L) and contact time (0-180 min) on the adsorption of dye were investigated and then optimized. The results indicated that with the increase of the adsorbent dosage from 0.02 to 0.1 g/L, the removal efficiency increased from 74.1% to 78.6%, and the adsorbed amount decreased from 148.25 to 31.44 mg/g. The maximum removal efficiency (77.54%) and adsorption capacity (31.02 mg/g) were observed at pH 2. Therefore, the general optimization conditions revealed that the maximum adsorption efficiency of dye was obtained in condition of initial concentration of 20 mg/L, contact time of 1 h and pH of solution equal 2. The adsorption isotherm and kinetic data were evaluated using a series of models. The pseudo-second order kinetic model and Freundlich isotherm model show the best fitting with experimental data with R2∼0.999.

scholarly journals Adsorption isotherms and kinetics of phosphate on waste mussel shell

2020 ◽  
Vol 16 (3) ◽  
pp. 393-399 ◽  
Author(s):  
Nur Atikah Abdul Salim ◽  
Mohd Hafiz Puteh ◽  
Abdull Rahim Mohd Yusoff ◽  
Noorul Hudai Abdullah ◽  
Mohamad Ali Fulazzaky ◽  
...  
Keyword(s):  
Kinetic Models ◽  
Langmuir Isotherm ◽  
Contact Time ◽  
Initial Conditions ◽  
Freundlich Isotherm ◽  
Liquid Solution ◽  
Physicochemical Characteristics ◽  
Isotherm Models ◽  
Mussel Shell ◽  
Adsorbent Dosage

In this study, removal of phosphate (PO43−) from aqueous solutions using waste mussel shell (WMS) was examined. The physicochemical characteristics of WMS were identified. In the batch experiments, the effects of contact time and adsorbent dosage (m) on the PO43− adsorption by the WMS were scrutinised. The maximum PO43− removal efficiency (E) was 83.4% at 144 h contact time for WMS dosage of 10 g. A comparison of kinetic models applied to the adsorption of PO43− onto WMS was evaluated using pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models. The experimental data was fitted well with the PSO kinetic model. In the isotherm studies, Langmuir and Freundlich isotherm models were applied. The Langmuir isotherm model was well described with the PO43− adsorption. The results indicated that WMS has a good potential to adsorb PO43− from water and thus could improve environmental quality. Furthermore, this study investigated on how the Langmuir isotherm for basic adsorption could be applied to predict E or required m under a given set of initial conditions (i.e., initial solute concentration, solution volume, and adsorbent dosage). This was accomplished by combining the Langmuir isotherm with mass balance of solutes between liquid solution and solid adsorbent phases.

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