Agar-agar impregnated on porous activated carbon as a new adsorbent for Pb(II) removal

2019 ◽  
Vol 79 (7) ◽  
pp. 1316-1326 ◽  
Author(s):  
Sabrine Saidi ◽  
Farouk Boudrahem ◽  
Idris Yahiaoui ◽  
Farida Aissani-Benissad
Keyword(s):  
Activated Carbon ◽  
Sorption Isotherms ◽  
Sorption Kinetics ◽  
Second Order ◽  
Sorption Properties ◽  
Point Of Zero Charge ◽  
Impregnation Ratio ◽  
Pseudo Second Order ◽  
Liquid Displacement ◽  
Porous Activated Carbon

Abstract This paper presents a new sorbent, agar-agar (AA), impregnated on porous activated carbon (AC) – and its Pb(II) sorption properties. The influence of impregnation ratio (AA/AC) on the Pb(II) ion sorption properties is studied in order to optimize this parameter. The developed AC-AA shows substantial capability to sorb Pb(II) ions from aqueous solutions and 75% represents the optimal impregnation ratio. The AC-AA sorbent with impregnation ratio of 75% was characterized by a liquid displacement method, point of zero charge pH (pHPZC), scanning electron microscopy and Fourier transform infrared spectroscopy. The effect of parameters such as sorbent dosage, pH, agitation time and initial Pb(II) concentration on Pb(II) removal were examined. In addition, sorption kinetics and sorption isotherms were determined. The maximum uptake of Pb(II) was about 242 mg/g at 25 °C, pH 5 and initial Pb(II) concentration of 100 mg/L. The kinetic data were fitted to the models of pseudo-first-order and pseudo-second-order, and the experimental results follow closely the pseudo-second-order model. The results also reveal that the experimental equilibrium is very close to those predicted by the Freundlich model. The developed AC-AA exhibits high Pb(II) sorption capacity, offering possibilities for future practical use.

scholarly journals Mass-transfer processes in the adsorption of crystal violet by activated carbon derived from pomegranate peels: Kinetics and thermodynamic studies

2020 ◽  
Vol 15 ◽  
pp. 155892502091984
Author(s):  
Moussa Abbas ◽  
Zahia Harrache ◽  
Mohamed Trari
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Crystal Violet ◽  
Agitation Speed ◽  
Second Order ◽  
Point Of Zero Charge ◽  
Order Kinetic ◽  
Solution Ph ◽  
Pseudo Second Order ◽  
Adsorbent Dose

This study investigates the potential use of activated carbon, prepared from pomegranate peels, as an adsorbent activated using H3PO4 and its ability to remove crystal violet from an aqueous solution. The adsorbent was characterized by the Brunauer–Emmett–Teller method (specific surface area: 51.0674 m2 g−1) and point of zero charge (pHPZC = 5.2). However, some examined factors were found to have significant impacts on the adsorption capacity of activated carbon derived from pomegranate peels such as the initial dye concentration (5–15 mg L−1), solution pH (2–14), adsorbent dose (1–8 g L−1), agitation speed (100–700 r/min), and temperature (298–338 K). The best adsorption capacity was found at pH 11 with an adsorbent dose of 1 g L−1, an agitation speed at 400 r/min, and a contact time of 45 min. The adsorption mechanism of crystal violet onto activated carbon derived from pomegranate peels was studied using the pseudo-first-order, pseudo-second-order, Elovich, and Webber–Morris diffusion models. The adsorption kinetics were found to rather follow a pseudo-second order kinetic model with a determination coefficient ( R2) of 0.999. The equilibrium adsorption data for crystal violet adsorbed onto activated carbon derived from pomegranate peels were analyzed by the Langmuir, Freundlich, Elovich, and Temkin models. The results indicate that the Langmuir model provides the best correlation with qmax capacities of 23.26 and 76.92 mg g−1 at 27°C and 32°C, respectively. The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters like the free energy, enthalpy, and entropy to predict the nature of adsorption process. The negative values Δ G0 (−5.221 to −1.571 kJ mol−1) and Δ H0 (−86.141 kJ mol−1) indicate that the overall adsorption is spontaneous and exothermic with a physisorption process. The adsorbent derived from pomegranate peels was found to be very effective and suitable for the removal of reactive dyes from aqueous solutions, due to its availability, low-cost preparation, and good adsorption capacity.

Adsorption of methylene blue from aqueous solution onto activated carbons developed from eucalyptus bark and Crataegus oxyacantha core

2016 ◽  
Vol 74 (9) ◽  
pp. 2021-2035 ◽  
Author(s):  
Mohammad Ali Zazouli ◽  
Ali Azari ◽  
Samaneh Dehghan ◽  
Razieh Salmani Malekkolae
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Activated Carbon ◽  
Activated Carbons ◽  
Second Order ◽  
Point Of Zero Charge ◽  
Polluted Water ◽  
Order Kinetic ◽  
Pseudo Second Order ◽  
Eucalyptus Bark

In this study, eucalyptus bark and Crataegus oxyacantha core-based activated carbon were synthesized and their morphological features characterized by scanning electron microscopy and Fourier transform infrared spectroscopy techniques. The efficiency of synthesized adsorbents in removal of methylene blue (MB) from aqueous solution was investigated in a series of batch experiments. Furthermore, the influences of various experimental factors involving the contact time, the initial dye concentration, the adsorbent dosage, and the pH of the dye solution were investigated. The point of zero charge (pHpzc) of the applied adsorbents was also determined. In addition, the experimental data were expressed by Langmuir, Freundlich and Tempkin isotherms and pseudo-first order and pseudo-second order kinetic models. Adsorption equilibrium of the two adsorbents was reached within 1 h for MB concentrations of 20 to 100 mg/L. The equilibrium data obtained at optimum conditions of MB sorption by eucalyptus bark activated carbon and Crataegus oxyacantha core activated carbon were best fitted to Tempkin and Langmuir isotherm models, respectively. Besides, it was revealed that the adsorption rate follows a pseudo-second order kinetic model. From the findings of this study, it can be postulated that these adsorbents could be of great potential as a new class of adsorbents for organic dye removal from polluted water.

scholarly journals Equilibrium and Kinetics Studies of Gentian Violet Dye Adsorption on to Activated Carbon Prepared From Aldhnan Hull

2017 ◽  
Vol 28 (1) ◽  
pp. 89
Author(s):  
Khudhair A. Kareem
Keyword(s):  
Activated Carbon ◽  
Gentian Violet ◽  
Equilibrium Constants ◽  
Dye Adsorption ◽  
Second Order ◽  
Point Of Zero Charge ◽  
Order Model ◽  
Batch Mode ◽  
Pseudo Second Order ◽  
Second Order Model

The present study investigated the key parameters and mechanism affecting the removal of Gentian Violet(GV) dye from aqueous medium, using Activated Carbon(AC) produced from hull of Aldhnan. The AC characterized by FTIR spectra to indicate the surface Characteristic groups of adsorbent affect the adsorption. The pH at point of zero charge showed the anionic nature of adsorbent surface and by using batch mode, the study considering the typical condition for adsorption of GV dye by the AC such as; effect of initial dye concentration, pH and contact time. The adsorption kinetics and equilibrium constants was achieved at 305K and the Langmuir isotherm model fit for the equilibrium data better than Freundlich model. Kinetics of adsorption was studied by testing the data in the pseudo first order (Lagergren Equation) and pseudo second order model and the adsorption of GV dye onto AC obeyed pseudo second order model. Thermodynamic studies exhibit that the adsorption reaction is endothermic in nature and spontaneous.

scholarly journals Sorption of the Direct Black 22 dye in alluvial soil

2020 ◽  
Vol 15 (4) ◽  
pp. 1
Author(s):  
Jeisiane Isabella da Silva Alexandre ◽  
Severino Martins dos Santos Neto ◽  
Artur Paiva Coutinho ◽  
Tássia Dos Anjos Tenório de Melo ◽  
Elizabeth Amaral Pastich Gonçalves ◽  
...  
Keyword(s):  
Experimental Data ◽  
Water Conservation ◽  
Groundwater Resources ◽  
Subsurface Layer ◽  
Alluvial Soil ◽  
Sorption Isotherms ◽  
Sorption Kinetics ◽  
Second Order ◽  
Order Kinetic ◽  
Direct Black 22

The semiarid region of Pernambuco has a large water deficit, leading the population to explore groundwater resources such as alluvial aquifers. The state of Pernambuco also stands out for having the second-largest textile manufacturing center in Brazil. However, the direct discharge of textile effluents from the region's industries has intensified the negative impacts on water conservation and alluvial soils. This work characterized the sorption of Direct Black 22 dye (DB22) in two layers of alluvial soil in the Capibaribe-PE basin. Batch experiments (kinetics and sorption isotherms) allowed the evaluation of the retention potential and mobility of this compound in this environment. Sorption kinetics were verified for stirring times of 0.25; 0.5; 1; 2; 4; 6; 8; 10; 12; 24; 48 and 72 hours and the experimental data was adjusted to the first- and second-order kinetic models. The isotherm occurred with concentrations of 1; 5; 10; 15; 20; 32.5 and 40 mg.L-1 and experimental data was adjusted to the linear, Freundlich and Langmuir models. The sorption kinetics of DB22 was best described by the second-order model, while the Freundlich and Linear models properly fitted sorption isotherms for Layers 1 and 2. The organic matter contents and the cation-exchange capacity of the soil layers influenced the sorption of the dye. The superficial layer privileges dye retention phenomena, while in the subsurface layer dye mobility phenomena prevail.

scholarly journals Adsorption of Cd (II), Pb (II) and Cr (III) on chemically modified Euterpe Oleracea biomass for the remediation of water pollution

2020 ◽  
Vol 43 ◽  
pp. e50263
Author(s):  
Affonso Celso Gonçalves Junior ◽  
Daniel Schwantes ◽  
Elio Conradi Junior ◽  
Juliano Zimmermann ◽  
Gustavo Ferreira Coelho
Keyword(s):  
Sorption Isotherms ◽  
Point Of Zero Charge ◽  
Heterogeneous Structure ◽  
Euterpe Oleracea ◽  
Sem Images ◽  
Chemically Modified ◽  
Pseudo Second Order ◽  
Ir Analysis ◽  
Central Composite ◽  
The Ideal

This study evaluated the use of Euterpe oleracea endocarp after chemical modification with H2O2, H2SO4 and NaOH for the removal of Cd2+, Pb2+ and Cr3+ from water. Therefore, the adsorbent was characterized for its chemical composition, Fourier Transform Infrared (FTIR) analysis, Scanning Electron Microscope (SEM) images, and pH of point of zero charge (pHPZC), thermal stability and porosimetry. Adsorption tests were conducted by using a Central Composite Design (CCD). Pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models evaluated the adsorption kinetics, and sorption isotherms were linearized according to Langmuir, Freundlich and Dubinin-Radushkevich. The effect of initial concentration, temperature in the process and the desorption were also analyzed. SEM results showed that the açaí adsorbents (or CA) had irregular and heterogeneous structure, and IR analysis evidenced the presence of hydroxyl, aliphatic, phenolic and carboxylic surface groups; both analyses indicate favorable adsorption characteristics. The pHPZC of the adsorbent is 4.41, 4.02 and 7.10 for CA modified with H2O2, H2SO4 and NaOH, respectively. The optimum adsorption conditions were pH 5.0, within 40 min, with 4 g L-1 as the ideal adsorbent dose. The predominance of chemisorption occurs, in mono and multilayer. The adsorption is only spontaneous for Cd2+ at 15 and 25°C. The CA has the potential to increase the removal efficiency of Cd, Pb and Cr, when chemically modified, particularly with H2O2 and H2SO4.

scholarly journals Removal of Malachite Green from Aqueous Solution by Activated Carbon Developed from Cocoa (Theobroma Cacao) Shell - A Kinetic and Equilibrium Studies

2011 ◽  
Vol 8 (s1) ◽  
pp. S363-S371 ◽  
Author(s):  
C. Theivarasu ◽  
S. Mylsamy
Keyword(s):  
Experimental Data ◽  
Activated Carbon ◽  
Malachite Green ◽  
Kinetic Models ◽  
Theobroma Cacao ◽  
Second Order ◽  
Order Kinetic ◽  
Equilibrium Studies ◽  
Initial Ph ◽  
Pseudo Second Order

The removal of malachite green (MG) by cocoa (Theobroma cacao) shell activated carbon (CSAC) was investigated in present study. Adsorption studies were performed by batch experiments as a function of process parameters such as initial pH, contact time, initial concentration and adsorbent dose. A comparison of kinetic models applied to the adsorption of MG on CSAC was evaluated for the pseudo-first order and pseudo-second order kinetic models. Results showed that the pseudo-second order kinetic model was found to correlate the experimental data well. The experimental equilibrium adsorption data was represented with Langmuir, Freundlich, Tempkin, Dubinin-Radushkevich and Flory-Huggins isotherms. The experimental data obtained in the present study indicated that activated carbon developed from cocoa shell can be attractive options for dye removal from waste water.

Kinetic, isotherm and thermodynamic studies of the adsorption of crystal violet by activated carbon from peanut shells

2013 ◽  
Vol 67 (4) ◽  
pp. 737-744 ◽  
Author(s):  
J. X. Zhang ◽  
L. L. Ou
Keyword(s):  
Activated Carbon ◽  
Crystal Violet ◽  
Correlation Coefficients ◽  
Second Order ◽  
Order Kinetic ◽  
Adsorption Capacities ◽  
Crystal Violet Dye ◽  
Peanut Shells ◽  
Pseudo Second Order ◽  
Good Agreement

The adsorption of crystal violet dye from aqueous solutions onto an activated carbon prepared from peanut shells was analyzed in this study. The effects of particle size, initial concentration, time and temperature on crystal violet removal were studied in batch experiments. Experimental results showed that the adsorption equilibrium was achieved within 100 min for all studied concentrations. Analysis of adsorption results showed that the adsorption isotherms could be well fitted to the Langmuir model. Kinetic parameters, rate constants, equilibrium adsorption capacities and related correlation coefficients for pseudo first-order and second-order kinetic models were calculated and discussed. The results revealed that the adsorption kinetics was in good agreement with the pseudo second-order equation. Thermodynamic parameters such as the change of Gibbs free energy (ΔG°), change of enthalpy (ΔH°) and change of entropy (ΔS°) have also been determined and it has been found that the adsorption process should be spontaneous, endothermic and physisorption in nature.

Lead Sorption by Carbon Nanofibers Grown on Powdered Activated Carbon — Kinetics and Equilibrium

NANO ◽  
2015 ◽  
Vol 10 (02) ◽  
pp. 1550017 ◽  
Author(s):  
Abdullah Al Mamun ◽  
Yehya M. Ahmed ◽  
Ma'an Fahmi R. AlKhatib ◽  
Ahmad Tariq Jameel ◽  
Mohammed Abdul Hakeem Abdul Rahman AlSaadi
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Carbon Nanofibers ◽  
Research Work ◽  
Palm Kernel ◽  
Solid Substrate ◽  
Second Order ◽  
Powdered Activated Carbon ◽  
Palm Kernel Shell ◽  
Pseudo Second Order

Carbon nanofibers (CNFs) were synthesized by using a safe and less hazardous method, compared to using floating catalysts in chemical vapor deposition (CVD) process. This process used C 2 H 2 as carbon source and oil palm kernel shell-based powdered activated carbon (PAC) as cheap solid substrate. Use of nickel ( Ni 2+) impregnated PAC as fixed substrate for the synthesis of CNF is one of the novelties of the research work accomplished by the authors. The PAC–CNFs porous nanocomposite product was used for the sorption of lead ions ( Pb 2+) from synthetic aqueous solution. Kinetics of Pb 2+ adsorption and isotherms were investigated by varying initial concentration of lead and contact time. PAC–CNFs were found to remove Pb 2+ better at acidic pH of about 5.5. Langmuir and Freundlich isotherms were applied to the sorption equilibrium data to find the best fitted model. Langmuir isotherm model with R2 = 0.965 fitted the adsorption data better than the Freundlich isotherm. The kinetic processes of Pb 2+ adsorption on CNFs were investigated by applying different kinetic models, namely zero-order, pseudo-first-order and pseudo-second-order. The pseudo-second-order rate equation exhibited the best results with R2 = 0.999, qe = 74.79 (mg/g) and K2 = 0.029 (min ⋅ g/mg). The novel nanocomposite product seemed to have the potential to remove Pb 2+ ions from aqueous solution.

scholarly journals Evaluation of the Marine AlgaeGracilariaand its Activated Carbon for the Adsorption of Ni(II) from Wastewater

2011 ◽  
Vol 8 (4) ◽  
pp. 1512-1521 ◽  
Author(s):  
A. Esmaeili ◽  
P. Beirami ◽  
S. Ghasemi
Keyword(s):  
Activated Carbon ◽  
Kinetic Studies ◽  
Second Order ◽  
Order Kinetic ◽  
Adsorption Model ◽  
Solution Ph ◽  
Isotherm Equation ◽  
Adsorption Data ◽  
Langmuir Isotherm Equation ◽  
Pseudo Second Order

The batch removal of Ni2+from aqueous solution and wastewater using marine dried (MD) red algaeGracilariaand its activated carbon (AC) was studied. For these experiments, adsorption of Ni2+was used to form two biomasses of AC and MD. Both methods used different pH values, biomass and initial concentration of Ni2+. Subsequently adsorption models and kinetic studies were carried out. The maximum efficiencies of Ni2+removal were 83.55% and 99.04% for MD and AC respectively developed from it. The experimental adsorption data were fitted to the Langmuir adsorption model. The nickel(II) uptake by the biosorbents was best described by pseudo-second order rate model. The kinetic studies showed that the heavy metal uptake was observed more rapidly by the AC with compared to MD. AC method developed from MD biomass exhibited higher biosorption capacity. Adsorption capacity is related to the pH of solution, pH 5.0 is optimal for nickel. The maximum efficiencies of Ni2+removal were for AC method. The capacity is related to the pH of solution, pH 5.0 is optimal for nickel. The equilibrium adsorption data are correlated by Langmuir isotherm equation. The adsorption kinetic data can be described by the second order kinetic models

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