scholarly journals Adsorption of Ni2+ from aqueous solution by magnetic Fe@graphite nano-composite

2016 ◽  
Vol 18 (4) ◽  
pp. 96-103 ◽  
Author(s):  
Wojciech Konicki ◽  
Rafał Pelka ◽  
Walerian Arabczyk
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Diffraction Method ◽  
Chemical Vapor ◽  
Bet Surface Area ◽  
Order Kinetic ◽  
Solution Ph ◽  
Transmission Electron ◽  
Order Kinetic Model ◽  
Nanocrystalline Iron

Abstract The removal of Ni2+ from aqueous solution by iron nanoparticles encapsulated by graphitic layers (Fe@G) was investigated. Nanoparticles Fe@G were prepared by chemical vapor deposition CVD process using methane as a carbon source and nanocrystalline iron. The properties of Fe@G were characterized by X-ray Diffraction method (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), Fourier Transform-Infrared Spectroscopy (FTIR), BET surface area and zeta potential measurements. The effects of initial Ni2+ concentration (1–20 mg L−1), pH (4–11) and temperature (20–60°C) on adsorption capacity were studied. The adsorption capacity at equilibrium increased from 2.96 to 8.78 mg g−1, with the increase in the initial concentration of Ni2+ from 1 to 20 mg L−1 at pH 7.0 and 20oC. The experimental results indicated that the maximum Ni2+ removal could be attained at a solution pH of 8.2 and the adsorption capacity obtained was 9.33 mg g−1. The experimental data fitted well with the Langmuir model with a monolayer adsorption capacity of 9.20 mg g−1. The adsorption kinetics was found to follow pseudo-second-order kinetic model. Thermodynamics parameters, ΔHO, ΔGO and ΔSO, were calculated, indicating that the adsorption of Ni2+ onto Fe@G was spontaneous and endothermic in nature.

UPTAKE BEHAVIOR OF ARSENATE FROM AQUEOUS SOLUTION USING FERRIC-COATED MESOPOROUS CERAMIC ADSORBENT

2016 ◽  
Vol 78 (5-3) ◽  
Author(s):  
Borano Te ◽  
Boonchai Wichitsathian ◽  
Chatpet Yossapol
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Physical Adsorption ◽  
Low Cost ◽  
Ceramic Filter ◽  
Order Kinetic ◽  
Solution Ph ◽  
Batch Mode ◽  
Order Kinetic Model ◽  
Arsenate Adsorption

Broken mesoporous ceramic filter was reutilized by coating with ferric solution through a simple loading method enhanced with heating at a moderate temperature for arsenate uptake from aqueous solution. BET, XRF, XRD, and SEM methods were applied for the adsorbent characterization. The adsorption study was conducted in a batch mode to investigate kinetics, isotherms, and the effect of solution pH and co-existing anions. The pseudo-second order kinetic model well fitted the experimental data (R2 = 0.9997). The maximum arsenate adsorption capacity (2.27 mg/g) was derived from the better described Langmuir isotherm model (R2 = 0.9992). The adsorbent expressed high arsenate adsorption capacity over a pH range of 4-10. The uptake behavior is a favorable and physical adsorption process based on the value of separation factor and mean sorption energy.  The presence of co-existing anions decreased the arsenate adsorption capacity in the following order: NO3-< SO42- < PO43-. The new ferric-coated mesoporous ceramic adsorbent could be an effective and low-cost adsorbent for arsenate removal from water. 

scholarly journals Study on the adsorption of methylene blue from aqueous solution using hydrogel glucomannan/graphene oxide

2021 ◽  
Vol 10 (1) ◽  
pp. 59-66
Author(s):  
Son Le Lam ◽  
Phu Nguyen Vinh ◽  
Hieu Le Trung ◽  
Tan Le Thua ◽  
Nhan Dang Thi Thanh ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Graphene Oxide ◽  
Adsorption Capacity ◽  
Organic Dyes ◽  
Dye Adsorption ◽  
Order Kinetic ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Glucomannan/graphene oxide (GM/GO) hydrogel was synthesized by using calcium hydroxide as the crosslinker. The synthesized material was characterized by using IR, XRD, SEM, EDX and RAMAN technology. The composite hydrogel was used for removal of organic dyes from aqueous solution. The results showed that the GM/GO hydrogel had a porous structure and a high adsorption capacity toward methylene blue (MB). The pseudo-second-order kinetic model could fit the rate equation of MB adsorption onto the GM/GO hydrogel. The adsorption of MB onto GM/GO hydrogel was a spontaneous process. In addition, the equilibrium adsorption isotherm data indicated that equilibrium data were fitted to the Langmuir isotherm and the maximum dye adsorption capacity was 198,69 mg.g-1. Moreover, the hydrogel was stable and easily recovered and adsorption capacity was around 97% of the initial saturation adsorption capacity after being used five times.

scholarly journals Preparation of bio-absorbents by modifying licorice residue via chemical methods and removal of copper ions from wastewater

2021 ◽  
Author(s):  
Xiaochun Yin ◽  
Nadi Zhang ◽  
Meixia Du ◽  
Hai Zhu ◽  
Ting Ke
Keyword(s):  
Adsorption Capacity ◽  
Copper Ions ◽  
Order Kinetic ◽  
Solution Ph ◽  
Chemical Methods ◽  
Simple Strategy ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Surface Active ◽  
Adsorption Desorption

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.

Characterization of Durian Seed Starch/PVOH Composite Hydrogel as a Potential Adsorbent for Removal of Hazardous Dyes

2014 ◽  
Vol 931-932 ◽  
pp. 286-290 ◽  
Author(s):  
W. Pimpa ◽  
C. Pimpa
Keyword(s):  
Adsorption Capacity ◽  
Synthetic Dyes ◽  
Order Kinetic ◽  
Solution Ph ◽  
Environment Friendly ◽  
Composite Hydrogels ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Durian Seed

The intention of this study was to prepare the environment friendly durian seed starch/polyvinyl alcohol (DSS/PVOH) composite hydrogels modified by chemical cross-linking with glutaraldehyde and to assess the adsorption potential of the DSS/PVOH composite hydrogels for the removal of the synthetic dyes from aqueous solution. The hydrogels were characterized by swelling behavior and scanning electron microscope (SEM). The effect of DSS content and initial dye solution pH on the adsorption capacity was studied conducting batch experiment system. The DSS/PVOH composite hydrogels consisting 3% DSS has optimum adsorption capacity of 3.411 mg/g (for methylene blue under the condition of pH 7) and 3.274 mg/g (for acid orange 8 under the condition of pH 2.5) at 24 h of contact time. The adsorptions were well fitted by the pseudo-second order kinetic model. It was indicated that the mechanism of removal predominant is effective for low dye concentrations, below 10 mg/l.

Metal Adsorbent Prepared from Coir Pith as Agricultural Waste: Adsorption of Zn(II) and Pb(II) from Aqueous Solution

2013 ◽  
Vol 545 ◽  
pp. 101-108 ◽  
Author(s):  
Kitirote Wantala ◽  
Nusavadee Pojananukij ◽  
Pongsert Sriprom ◽  
Tinnakorn Kumsaen ◽  
Arthit Neramittagapong ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Calcination Temperature ◽  
Ph Value ◽  
Agricultural Waste ◽  
Initial Solution ◽  
Order Kinetic ◽  
Solution Ph ◽  
Freundlich Isotherms ◽  
Coir Pith

Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as an adsorbent. The extended adsorption conditions were investigated as a function of calcination temperature, contact time, adsorbent size, initial pH of solution and initial Zn(II) and Pb(II) concentrations. The adsorption capacity increased rapidly in first 5 minute and reached equilibrium in 120 minutes for Zn(II) and 10 minutes for Pb(II). In case of Zn(II); the results showed that the calcination temperature of modified coir pith above 600oC gave the higher adsorption capacity. The sizes of modified coir pith have no effect on the adsorption capacity. The adsorption capacity increased with increasing initial solution pH value. In case of Pb(II); the calcination temperature of modified coir pith showed no effect on the adsorption capacity. The sizes of modified coir pith showed a little effect on the adsorption capacity. The adsorption capacity increased with increasing of initial solution pH value up to pH of 3 and then stable. The results also corresponded with the Langmuir and Freundlich isotherms and pseudo second order kinetic adsorption models. The modified coir pith gave a higher Zn(II) and Pb(II) adsorption capacity of 29.33 mg Zn(II)/g adsorbent and 36.50 mg Pb(II)/g adsorbent, respectively.

scholarly journals Comparison of Adsorptive Removal of Total Nitrogen (T-N) and Total Phosphorous (T-P) in Aqueous Solution using Granular Activated Charcoal (GAC)

2013 ◽  
Vol 9 (1) ◽  
pp. 1822-1836
Author(s):  
Keon Sang Ryoo ◽  
Jong-Ha Choi ◽  
Yong Pyo Hong
Keyword(s):  
Aqueous Solution ◽  
Kinetic Model ◽  
Adsorption Capacity ◽  
Total Nitrogen ◽  
Activated Charcoal ◽  
Adsorption Equilibrium ◽  
Order Kinetic ◽  
Total Phosphorous ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The present study is to explore the possibility of utilizing granular activated charcoal (GAC) for the removal of total phosphorous (T-P) and total nitrogen (T-N) in aqueous solution. Batch adsorption studies were carried out to determine the influences of various factors like initial concentration, contact time and temperature. The adsorption data showed that GAC has a similar adsorption capacity for both T-N and T-P. The adsorption degree of T-N and T-P on GAC was highly concentration dependent. It was found that the adsorption capacity of GAC is quite favorable at a low concentration. At concentrations of 1.0 mg L-1 of T-P and 2.0 mg L-1 of T-N, approximately 97 % of adsorption was achieved by GAC. The equilibrium data were fitted well to the Langmuir isotherm model. The pseudo-second-order kinetic model appeared to be the better-fitting model because it has higher R2 compared with the pseudo-first-order and intra-particle kinetic model. The theoretical adsorption equilibrium qe,cal from pseudo-second-order kinetic model were relatively similar to the experimental adsorption equilibrium qe,exp. To evaluate the effect of thermodynamic parameters at different temperatures, the change in free energy ΔG, the enthalpy ΔH and the entropy ΔS were estimated. Except for adsorption of T-P at 278 K, the ΔG values obtained were all negative at the investigated temperatures. It indicates that the present adsorption system occurs spontaneously. The adsorption process of T-N by GAC was exothermic in nature, whereas T-P showed endothermic behavior. In addition, the positive values of ΔS imply that there was the increase in the randomness of adsorption of T-N and T-P at GAC-solution interface.  

scholarly journals SURFACE MODIFICATION OF CANARIUM OVATUMENGL.(PILI) SHELL AS ADSORBENT OF LEAD(Pb2+) FROM AQUEOUS SOLUTION

2021 ◽  
Author(s):  
Ernesto Jr. S. Cajucom ◽  
◽  
Lolibeth V. Figueroa ◽  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Cost Effective ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Carboxylic Groups ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Surface Modified

This study was carried out to investigate the efficiency of raw pili shell (RPS) and the surface modified pili shell using EDTA (EMPS) and oxalic acid (OMPS). A comparative study on the adsorption capacity of the adsorbents was performed against lead (Pb2+) from aqueous solution. The adsorbents were characterized by FTIR, which showed higher peak of adsorption bands of carboxylic groups on the acid modified pili shells. Scanning electron microscope orSEM was also used to describe the surface morphology of the adsorbents. The linear form of Langmuir and Freundlich models were applied to represent adsorption data. The calculated equilibrium data of Pb (II) best fitted to Langmuir compare to Freundlich isotherm model with maximum adsorption capacity (qmax) of 27.03 mg/g and 45.45 mg/g using EMPS and OMPS, respectively. Kinetic sorption models were used to determine the adsorption mechanism and the kinetic data of all the adsorbents correlated (R2=1) wellwith the pseudo second order kinetic model. Among the three adsorbents, OMPS shown higher percent removal of lead compared to RPS and EMPS. The large adsorption capacity rate indicated that chemically modified pili shell in present study has great potential to be used as a cost-effective adsorbent for the removal of lead ions from the water.

scholarly journals Nano-TiO2, ultrasound and sequential nano-TiO2/ultrasonic degradation of N-acetyl-para-aminophenol from aqueous solution

2017 ◽  
Vol 15 (6) ◽  
pp. 1015-1027 ◽  
Author(s):  
Olushola S. Ayanda ◽  
Simphiwe M. Nelana ◽  
Leslie F. Petrik ◽  
Eliazer B. Naidoo
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Removal Efficiency ◽  
Treatment Process ◽  
Freundlich Isotherm ◽  
Attenuated Total Reflection ◽  
Order Kinetic ◽  
Nano Tio2 ◽  
Transmission Electron ◽  
Order Kinetic Model

Abstract The application of nano-TiO2 as adsorbent combined with ultrasound for the degradation of N-acetyl-para-aminophenol (AAP) from aqueous solution was investigated. The nano-TiO2 was characterized by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR). Experimental results revealed that the adsorption of AAP by nano-TiO2 fitted the pseudo-second-order kinetic model, the equilibrium could be explained by the Freundlich isotherm and the treatment process is exothermic. The optimum removal efficiency of AAP (128.89 mg/g (77.33%)) was achieved at pH 4 when 0.03 g of nano-TiO2 was mixed with 50 mL of 100 mg/L AAP aqueous solution at ambient temperature, 60 min contact time, and a stirring speed of 120 rpm. Ultrasound at 20 kHz and pH 3 was favorable and it resulted in 52.61% and 57.43% removal efficiency with and without the addition of nano-TiO2, respectively. The degradation of AAP by ultrasound followed by nano-TiO2 treatment resulted in approximately 99.50% removal efficiency. This study showed that a sequential ultrasound and nano-TiO2 treatment process could be employed for the removal of AAP or other emerging water and wastewater contaminants.

scholarly journals Modified Vermiculite as Adsorbent of Hexavalent Chromium in Aqueous Solution

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 749
Author(s):  
Celia Marcos ◽  
Valeria Medoro ◽  
Alaa Adawy
Keyword(s):  
Adsorption Capacity ◽  
Adsorption Energy ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Ion Chemistry ◽  
Solution Ph ◽  
Cooperative Process ◽  
Order Kinetic Model ◽  
Initial Adsorption ◽  
Initial Adsorption Rate

The aim of this study was to investigate the efficiency of removing Cr6+ from aqueous solutions using two exfoliated vermiculite: (1) heated abruptly at 1000 °C and (2) irradiated with microwave radiation. The effects investigated were contact time, adsorbate concentration and initial Cr6+ concentration. The adsorption with both exfoliated vermiculites was well described by the DKR isotherm, indicative of a cooperative process and with the pseudo second order kinetic model. The Kd value for the two exfoliated vermiculites was similar, 0.2 ·1010 μg/Kg. The maximum adsorption capacity of Cr6+ with thermo-exfoliated vermiculite, 2.81 mol/g, was much higher than with microwave irradiated vermiculite, 0.001 mol/g; both values were obtained with 0.5 g of vermiculite in contact with distilled water enriched with 1 ppm of Cr6+ for 24 h. Factors such as ion chemistry, the solution pH and ionic strength, influence the values of capacity, adsorption energy and initial adsorption rate values of the exfoliated vermiculite. In addition, these values depended on the exfoliation process, being the adsorption capacity highest with abrupt heating of vermiculite, while the adsorption energy and rate values showed just a slight increase with microwave irradiation. This aspect is important to select the most suitable vermiculite modification treatment to use it as an adsorbent.

scholarly journals Dye removal from aqueous solution by raw maize corncob and H3PO4 activated maize corncob

2017 ◽  
Vol 8 (2) ◽  
pp. 214-224 ◽  
Author(s):  
M. Farnane ◽  
H. Tounsadi ◽  
A. Machrouhi ◽  
A. Elhalil ◽  
F. Z. Mahjoubi ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Order Kinetic ◽  
Solution Ph ◽  
Adsorption Performance ◽  
Adsorption Capacities ◽  
Monolayer Adsorption ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Best Fit

AbstractThe focus of this study is the investigation of removal ability of methylene blue (MB) and malachite green (MG) dyes from aqueous solution by raw maize corncob (RMC) and H3PO4 activated maize corncob (AMC). Maize corncobs were carbonized at 500 °C for 2 h, and then impregnated at a phosphoric acid to maize corncob ratio of 2.5 g/g. The impregnated maize corncob was activated in a tubular vertical furnace at 450 °C for 2 h. Samples were characterized by different methods. Adsorption experiments were carried out as a function of solution pH, adsorbent dosage, contact time, initial concentration of dyes and the temperature. Experimental results show that the activation of maize corncob boosts four times the adsorption performance for the selected dyes. The adsorption process is very rapid and was pH dependent with high adsorption capacities in the basic range. The kinetic data were fitted with the pseudo-second-order kinetic model. The best fit of equilibrium data was obtained by the Langmuir model with maximum monolayer adsorption capacities of 75.27 and 271.19 mg/g for MB, 76.42 and 313.63 mg/g for MG, respectively, in the case of RMC and AMC. The temperature did not have much influence on the adsorption performance.

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