scholarly journals Single-Step Hydrothermal Synthesis of Biochar from H3PO4-Activated Lettuce Waste for Efficient Adsorption of Cd(II) in Aqueous Solution

Molecules ◽  
2022 ◽  
Vol 27 (1) ◽  
pp. 269
Author(s):  
Quyun Chen ◽  
Tian C. Zhang ◽  
Like Ouyang ◽  
Shaojun Yuan
Keyword(s):  
Heavy Metals ◽  
Aqueous Solution ◽  
Low Temperature ◽  
Low Cost ◽  
Hydrothermal Carbonization ◽  
Single Step ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Solution Ph ◽  
Order Kinetic Model

Developing an ideal and cheap adsorbent for adsorbing heavy metals from aqueous solution has been urgently need. In this study, a novel, effective and low-cost method was developed to prepare the biochar from lettuce waste with H3PO4 as an acidic activation agent at a low-temperature (circa 200 °C) hydrothermal carbonization process. A batch adsorption experiment demonstrated that the biochar reaches the adsorption equilibrium within 30 min, and the optimal adsorption capacity of Cd(II) is 195.8 mg∙g−1 at solution pH 6.0, which is significantly improved from circa 20.5 mg∙g−1 of the original biochar without activator. The fitting results of the prepared biochar adsorption data conform to the pseudo-second-order kinetic model (PSO) and the Sips isotherm model, and the Cd(II) adsorption is a spontaneous and exothermic process. The hypothetical adsorption mechanism is mainly composed of ion exchange, electrostatic attraction, and surface complexation. This work offers a novel and low-temperature strategy to produce cheap and promising carbon-based adsorbents from organic vegetation wastes for removing heavy metals in aquatic environment efficiently.

scholarly journals Batch Adsorption of Safranin Dye from an Aqueous Solution of Balanites aegyptiaca Seed Coats

2020 ◽  
pp. 48-54
Author(s):  
Buhari Magaji ◽  
Aisha U. Maigari ◽  
Usman A. Abubakar ◽  
Mukhtar M. Sani ◽  
Amina U. Maigari
Keyword(s):  
Aqueous Solution ◽  
Correlation Coefficient ◽  
Low Cost ◽  
Kinetic Studies ◽  
Second Order ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Seed Coats

This study was aimed at using Balanite aegyptiaca seed coats activated carbon (BAAC) as a potential adsorbent to remove safranin dye from aqueous solution. BAAC was prepared from Balanite aegyptiaca seed coats using a one-step procedure with 67.27% yield, 3.23% ash content, 695 m2/g surface area and 203 mg/g iodine number. The FTIR spectroscopy revealed O-H, N-H, C-H, C=C, C-O-H stretching vibrations. The influences of agitation time, initial dye concentration and adsorbent dose were studied in batch experiments at room temperature. The adsorptions were rapid at the first 15 minutes of agitation, with the uptake of 2.746 mg/kg. The adsorption equilibrium was achieved at 90 minutes of agitation. Kinetic studies showed good correlation coefficient for both pseudo-first order and pseudo-second-order kinetics model but fitted well into pseudo-second order kinetic model. The adsorption data fitted well into Langmuir isotherm with correlation coefficient (R2) very close to unity and Langmuir maximum adsorption constant, qm  1.00. Thus, the fitting into Langmuir indicates monolayer coverage on the adsorbents. The results showed that BAAC has the potential to be applied as alternative low-cost adsorbents in the remediation of dye contamination in wastewater.

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 Optimization of process parameters for heavy metals biosorption onto mustard waste biomass

2016 ◽  
Vol 14 (1) ◽  
pp. 175-187 ◽  
Author(s):  
Lăcrămioara (Negrilă) Nemeş ◽  
Laura Bulgariu
Keyword(s):  
Heavy Metals ◽  
Aqueous Media ◽  
Order Kinetic ◽  
Waste Biomass ◽  
Solution Ph ◽  
Biosorption Process ◽  
Optimization Of Process Parameters ◽  
Removal Of Heavy Metals ◽  
Equilibrium Data ◽  
Order Kinetic Model

AbstractMustard waste biomass was tested as a biosorbent for the removal of Pb(II), Zn(II) and Cd(II) from aqueous solution. This strategy may be a sustainable option for the utilization of such wastes. The influence of the most important operating parameters of the biosorption process was analyzed in batch experiments, and optimal conditions were found to include initial solution pH 5.5, 5.0 g biosorbent/L, 2 hours of contact time and high temperature. Kinetics analyses show that the maximum of biosorption was quickly reached and could be described by a pseudo-second order kinetic model. The equilibrium data were well fitted by the Langmuir model, and the highest values of maximum biosorption capacity were obtained with Pb(II), followed by Zn(II) and Cd(II). The thermodynamic parameters of the biosorption process (ΔG, ΔH and ΔS) were also evaluated from isotherms. The results of this study suggest that mustard waste biomass can be used for the removal of heavy metals from aqueous media.

Biosorption of hexavalent chromium from aqueous solution by polyethyleneimine-modified ultrasonic-assisted acid hydrochar from Sargassum horneri

2020 ◽  
Vol 81 (6) ◽  
pp. 1114-1129 ◽  
Author(s):  
Jun Wang ◽  
Qinglong Xie ◽  
Ao Li ◽  
Xuejun Liu ◽  
Fengwen Yu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Batch Adsorption ◽  
Crosslinking Reaction ◽  
Order Kinetic ◽  
Adsorption Capacities ◽  
Initial Ph ◽  
Ultrasonic Assisted ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Abstract In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.

Assessment of Urtica as a low-cost adsorbent for methylene blue removal: kinetic, equilibrium, and thermodynamic studies

2015 ◽  
Vol 69 (7) ◽  
Author(s):  
Mohammad Peydayesh ◽  
Mojgan Isanejad ◽  
Toraj Mohammadi ◽  
Seyed Mohammad Reza Seyed Jafari
Keyword(s):  
Methylene Blue ◽  
Adsorption Process ◽  
Low Cost ◽  
Cost Effective ◽  
Sem Analysis ◽  
Order Kinetic ◽  
Solution Ph ◽  
Factors Affecting ◽  
Order Kinetic Model ◽  
Mb Adsorption

AbstractMethylene blue (MB) removal using eco-friendly, cost-effective, and freely available Urtica was investigated. The morphology of the adsorbent surface and the nature of the possible Urtica and MB interactions were examined using SEM analysis and the FTIR technique, respectively. Various factors affecting MB adsorption such as adsorption time, initial MB concentration, temperature, and solution pH were investigated. The adsorption process was analysed using different kinetic models and isotherms. The results showed that the MB adsorption kinetic follows a pseudo-second-order kinetic model and the isotherm data fit the Langmuir isotherm well. Thermodynamic parameters, such as ΔG°, ΔH°, and ΔS°, were also evaluated, and the results indicated that the adsorption process is endothermic and spontaneous in nature. The MB adsorption capacity of Urtica was found to be as high as 101.01 mg g

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.

scholarly journals Pine cones powder for the adsorptive removal of copper ions from water

2021 ◽  
pp. 1-1
Author(s):  
Redouane Ouafi ◽  
Anass Omor ◽  
Younes Gaga ◽  
Mohamed Akhazzane ◽  
Mustapha Taleb ◽  
...  
Keyword(s):  
Particle Size ◽  
Copper Ions ◽  
Low Cost ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Solution Ph ◽  
Order Kinetic Model ◽  
Endothermic Process ◽  
Environmentally Friendly Process ◽  
Pine Cones

This research investigates the adsorption potential of pine cones powder (PCP) for the removal of copper ions (Cu(II)) from aqueous solutions. The process of adsorption was reasonably fast to be completed within a time of 60 min. The pseudo-second order kinetic model describes properly the Cu(II) adsorption by PCP. The adsorbent was characterised by various instrumental techniques and batch experiments were conducted to investigate the effect of PCP dose, solution pH, particle size and initial Cu(II) concentration on adsorption efficiency. Optimum Cu(II) removal occurred at a slightly acidic pH, with a particle size less than 100 ?m. The effective PCP dose was estimated to be 36 g.L-1. The increase in the initial concentration of Cu (II) was accompanied by a reduction in the rate of its reduction by almost half. The Langmuir model was the best fitting isotherm with a maximum adsorption capacity of 9.08 mg.g-1. The thermodynamic parameters values showed that the Cu(II) adsorption was a spontaneous and endothermic process. The results of this research suggest that Cu(II) could be removed through an environmentally friendly process using PCP as low-cost natural wastes.

scholarly journals Adsorption Properties of Au(III) and Cu(II) from Aqueous Solution Using Chemically Treated Sheep Wool

2021 ◽  
Vol 333 ◽  
pp. 04006
Author(s):  
Solongo Enkhzaya ◽  
Koichiro Shiomori ◽  
Bolormaa Oyuntsetseg
Keyword(s):  
Aqueous Solution ◽  
Chemical Treatment ◽  
Low Cost ◽  
High Capacity ◽  
Copper Ion ◽  
Order Kinetic ◽  
Rate Determining Step ◽  
Chemically Treated ◽  
Order Kinetic Model ◽  
Sheep Wool

Au(III) and Cu(II) adsorption from aqueous solution were carried out using sheep wools with chemical treatments, by NaOH, Na2S, NaHSO3, and NaBH4 aqueous solution. The fibrous wool was transformed into a film like structures after the chemical treatment using Na2S. The sheep wool and the chemically treated sheep wool adsorbed selectively Au(III) from Au-Cu binary aqueous solution and the presence of copper ion had no effect on the Au(III) adsorption. Au(III) adsorbed substantially at low pH range. The kinetic experimental data fitted well with the pseudo-second-order kinetic model and the adsorption amount of Au(III) increased with time and reached a plateau after 12 h. The kinetic analysis suggests that rate determining step of Au adsorption would be chemisorption due to the formation of a monolayer on the wool surface. Sheep wool is a low cost, eco-friendly material, and has a high capacity of adsorption, and could be used as a biosorbent for precious and heavy metals by modification of appropriate chemical treatment.

Study of the kinetics and the adsorption isotherm of cadmium(II) from aqueous solution using green algae (Ulva lactuca) biomass

2015 ◽  
Vol 72 (9) ◽  
pp. 1505-1515 ◽  
Author(s):  
H. Asnaoui ◽  
A. Laaziri ◽  
M. Khalis
Keyword(s):  
Aqueous Solution ◽  
Metal Ions ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Second Order ◽  
Ulva Lactuca ◽  
Order Kinetic ◽  
Solution Ph ◽  
Algae Biomass ◽  
Pseudo Second Order

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.

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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