Biosequestration of chromium (VI) from aqueous medium using carbonaceous adsorbents derived from Eichhornia crassipes

Abstract Utilization of the biochar that are derived from Eichhornia crassipes (water hyacinth) as biosorbent for Cr (VI) adsorption was investigated. The biochar was characterized before and after Cr (VI) adsorption by SEM, FTIR and EDX. The influencing parameters viz., solution pH, solute concentrations, reaction duration, adsorbent dose and size have been examined. The most favorable conditions for Cr (VI) removal were found to be pH = 2.0, adsorbent size = 0.2 mm, adsorbent dosage = 2.5g/100ml, adsorbate/solute concentration = 100mg/L of Cr (VI) at 25ºC at 250 rpm. Rate of adsorption was rapid and equilibrium was reached at 36 hours. The equilibrium relationship between the sorbent and sorbate was determined using the isotherms Langmuir, Freundlich and Temkin models. The Langmuir dimensionless constant (KR) for each of the solute concentration was ranged between 0 and 1, it indicates the favourable adsorption of Cr (VI) onto the adsorbent. Adsorption data was very well explained through Langmuir isotherm where sorption occurs on monolayer with the maximum biosorption capacity of 55.55 mg/g. Adsorption rate and its mechanisms were elucidated through kinetic studies viz., Pseudo first order, second order, elovich and intra particle diffusion models. On comparison with various kinetic models, results fitted excellently with pseudo second order model (R2 = 0.999). It suggests that Cr (VI) adsorption by could be better described by chemisorption which involves sharing of electrons between adsorbents and adsorbate. Hence, the biochar derived from E. crassipes are efficiently used as an ecofriendly biosorbent for the management of Cr (VI) rich waste water.

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

E-Journal of Chemistry ◽

10.1155/2011/137484 ◽

2011 ◽

Vol 8 (4) ◽

pp. 1512-1521 ◽

Cited By ~ 5

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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Removal of Direct Yellow 50 From Aqueous Solutions Using Chitosan-ISO-Vanillin Derivatives Chelating Polymers

10.21203/rs.3.rs-129329/v1 ◽

2020 ◽

Author(s):

Eman Alabbad

Keyword(s):

Contact Time ◽

Removal Rate ◽

Second Order ◽

Rate Equations ◽

Order Kinetic ◽

Solution Ph ◽

Modified Chitosan ◽

Intra Particle Diffusion ◽

Pseudo Second Order ◽

Living Organisms

Abstract Background Water contamination has increasingly become a significant problem affecting the welfare of living organisms perceived to be aquatic beneficiaries. The nature and origin of the contaminant always determines the purification techniques. The most common contaminants in wastewater include organic compounds such as dyes that must be eliminated to enhance water purity and safety.Result The results indicate that the removal of DY50 by the modified chitosan was affected by the solution pH, sorbent dosage, initial DY50 concentration, contact time, and temperature. The experimental data were fitted to the Langmuir, Freundlich, and Temkin isotherms, and Langmuir isotherm showed the best fit. The kinetic data were fitted to the pseudo-first-order and pseudo-second-order rate equations. The removal rate was 97.9% by chemisorption components after the three hours at about 0.05 g of sorbent dose and 100 ppm of the Direct Yellow 50 dye initial concentration. The adsorption behavior of the modified chitosan for the removal of DY50 was well-described using the pseudo-second-order kinetic model, Intraparticle diffusion analysis was also conducted. The thermodynamic properties such as free energy (∆G), enthalpy (∆H), and entropy (∆S), in addition to the intra-particle diffusion rate were similarly defined.Conclusion The pH, initial DY50 concentration, sorbent dosage, adsorption temperature, and contact time had a significant effect on the adsorption of DY50 by chitosan-iso-vanillin.

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Kinetic Studies of Adsorption of Disperse Blue 2BLN from Aqueous Solution by Expanded Graphite

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.148-149.357 ◽

2011 ◽

Vol 148-149 ◽

pp. 357-360

Author(s):

Jin Bo Huang ◽

Min Cong Zhu ◽

Zhi Fang Zhou ◽

Hong Xia Zhang

Keyword(s):

Aqueous Solution ◽

Room Temperature ◽

Ph Value ◽

Expanded Graphite ◽

Kinetic Studies ◽

Second Order ◽

Batch Adsorption ◽

Initial Ph ◽

Intra Particle Diffusion ◽

Pseudo Second Order

Expanded graphite (EG) was prepared by microwave irradiation and evaluated as adsorbent for the removal of disperse blue 2BLN (DB) from aqueous solution by the batch adsorption technique under different conditions of initial pH value, adsorbent dosage, initial dye concentration and contact time. The experimental data were analyzed considering pseudo-first-order, pseudo-second-order and intra-particle diffusion approaches. The adsorption kinetics at room temperature could be expressed by the pseudo second order model very well. The results indicate that the adsorption rate is fast enough and more than eighty percent of the adsorbed DB can be removed in the first 15 min at room temperature, which makes the process practical for industrial application.

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Kinetic studies of phosphate adsorption onto construction solid waste (CSW)

Water Quality Research Journal ◽

10.2166/wqrjc.2014.013 ◽

2014 ◽

Vol 49 (4) ◽

pp. 307-318 ◽

Cited By ~ 4

Author(s):

C. Liu ◽

Y. Yang ◽

N. Wan

Keyword(s):

Solid Waste ◽

Low Cost ◽

Kinetic Studies ◽

Second Order ◽

Phosphate Removal ◽

Alkaline Condition ◽

Phosphate Adsorption ◽

Particle Diffusion ◽

Order Kinetic ◽

Intra Particle Diffusion

Adsorption of phosphate onto construction solid waste (CSW) was investigated in a batch system. CSW as an inescapable by-product of the construction and demolition process, was used as a composite adsorbent for the removal of phosphate in this study. The adsorption kinetics was investigated under various parameters such as contact time, pH, CSW dosage, initial phosphate concentration and particle size. Greater percentage of phosphate was removed with decrease in the initial concentration and increase in the amount of CSW used. Adsorption of phosphate was pH dependent, and maximum phosphate immobilisation capacity was obtained in alkaline condition. Lagergren ﬁrst-order, second-order, intra-particle diffusion and external diffusion model were used to test the experimental data. Kinetic analysis showed that the adsorption was best ﬁtted with the pseudo-second-order kinetic model. Adsorption mechanism studies revealed that both external mass transfer and intra-particle diffusion had rate limiting effects on the removal process. These results demonstrated that the CSW could be used as a low-cost adsorbent media for phosphate removal, and the data were relevant for optimal design of wastewater treatment plants.

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Adsorption behavior of Cd2+ ions using hydroxyapatite (HAp) powder

Green Processing and Synthesis ◽

10.1515/gps-2018-0031 ◽

2018 ◽

Vol 7 (5) ◽

pp. 409-416 ◽

Cited By ~ 1

Author(s):

Nguyen Thi Thom ◽

Dinh Thi Mai Thanh ◽

Pham Thi Nam ◽

Nguyen Thu Phuong ◽

Claudine Buess-Herman

Keyword(s):

Heavy Metals ◽

Adsorption Capacity ◽

Negative Impact ◽

Second Order ◽

Solution Ph ◽

First Order ◽

Monolayer Adsorption ◽

Adsorption Data ◽

Intra Particle Diffusion ◽

Pseudo Second Order

Abstract Pollution of heavy metals in water can affect the health of humans and the environment; therefore, removal of heavy metal ions is getting the attention of scientists. To reduce the negative impact of heavy metals on human health and the environment, Cd2+ ions present in water were treated using hydroxyapatite (HAp) as adsorbent. The effects of contact time, initial Cd2+ concentration, solution pH, and adsorbent mass on the adsorption capacity and efficiency of HAp were investigated. Cd2+ uptake was quantitatively evaluated using Langmuir and Freundlich adsorption isotherms. The maximum monolayer adsorption capacity was 119 mg/g. The experimental adsorption data were analyzed using three kinetic models: Lagergren’s pseudo-first-order law, McKay and Ho’s pseudo-second-order law, and the intra-particle diffusion model. The results showed that the Cd2+ removal process follows the pseudo-second-order law.

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Exploring Adsorption Process of Lead (II) and Chromium (VI) Ions from Aqueous Solutions on Acid Activated Carbon Prepared from Juniperus procera Leaves

Processes ◽

10.3390/pr7040217 ◽

2019 ◽

Vol 7 (4) ◽

pp. 217 ◽

Cited By ~ 17

Author(s):

Ismat H. Ali ◽

Mohammed K. Al Mesfer ◽

Mohammad I. Khan ◽

Mohd Danish ◽

Majed M. Alghamdi

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Kinetic Studies ◽

Ion Concentration ◽

Isotherm Models ◽

Solution Ph ◽

Chromium Vi ◽

Biosorption Process ◽

Endothermic Process ◽

Juniperus Procera

The adsorption potential of acid activated carbon prepared from leaves of Juniperus procera to remove Pb(II) and Cr(VI) toxic ions from aqueous solutions was investigated. The effects of solution pH, adsorbent mass, contact time, initial ion concentration and temperature on the biosorption process were studied, and the optimum conditions were determined. Moreover, Langmuir, Freundlich, Temkin and Dubinin–Radushkevich adsorption isotherm models were applied to analyze adsorption data. Thermodynamic parameters for the adsorption processes were calculated. Adsorption was found to be a spontaneous and endothermic process. In addition, kinetic studies revealed a pseudo-first order kinetics biosorption process. The obtained results suggest that acid activated Juniperus procera leaves powder can be used as a cheap, efficient and environmentally friendly adsorbent material with high removal efficiency up to 98% for Pb(II) and 96% for Cr(VI) at 0.80 and 1.00 g/100 mL, respectively. The duration of the process was 100 min and 120 min for Pb(II) and Cr(VI) ions, respectively. The morphology of the of prepared activated carbon was investigated by scanning electron microscope (SEM).

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Study on an effective industrial waste-based adsorbent for the adsorptive removal of phosphorus from wastewater: equilibrium and kinetics studies

Water Science & Technology ◽

10.2166/wst.2016.021 ◽

2016 ◽

Vol 73 (8) ◽

pp. 1891-1900 ◽

Cited By ~ 4

Author(s):

Ruzhen Xie ◽

Yao Chen ◽

Ting Cheng ◽

Yuguo Lai ◽

Wenju Jiang ◽

...

Keyword(s):

Industrial Waste ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Order Kinetic ◽

Solution Ph ◽

Before And After ◽

Equilibrium And Kinetics ◽

Equilibrium Data ◽

Intra Particle Diffusion ◽

Ph Range

In this work, an effective adsorbent for removing phosphate from aqueous solution was developed from modifying industrial waste — lithium silica fume (LSF). The characterization of LSF before and after modification was investigated using an N2 adsorption–desorption technique (Brunauer–Emmett–Teller, BET), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Studies were conducted to investigate the effect of adsorbent dose, initial solution pH, contact time, phosphate concentration, and temperature on phosphate removal using this novel adsorbent. The specific surface area for modified LSF (LLSF) is 24.4024 m2/g, improved 69.8% compared with unmodified LSF. XRD result suggests that the lanthanum phosphate complex was formed on the surface of LLSF. The maximum phosphate adsorption capacity was 24.096 mg P/g for LLSF, and phosphate removal was favored in the pH range of 3–8. The kinetic data fitted pseudo-second-order kinetic equation, intra-particle diffusion was not the only rate controlling step. The adsorption isotherm results illustrated that the Langmuir model provided the best fit for the equilibrium data. The change in free energy (△G0), enthalpy (△H0) and entropy (△S0) revealed that the adsorption of phosphate on LLSF was spontaneous and endothermic. It was concluded that by modifying with lanthanum, LSF can be turned to be a highly efficient adsorbent in phosphate removal.

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Adsorption Ability for Toxic Chromium (VI) Ions in Aqueous Solution of Some Modified Oyster Shell Types

Bioinorganic Chemistry and Applications ◽

10.1155/2020/2435777 ◽

2020 ◽

Vol 2020 ◽

pp. 1-17

Author(s):

Thuy Chinh Nguyen ◽

Xuan Thai Nguyen ◽

Do Mai Trang Tran ◽

Quoc Trung Vu ◽

Van Hai Nguyen ◽

...

Keyword(s):

Ethylenediaminetetraacetic Acid ◽

Oyster Shell ◽

Second Order ◽

Ion Adsorption ◽

Adsorption Ability ◽

First Order ◽

Chromium Vi ◽

Reaction Models ◽

Before And After ◽

Set Up

In this paper, the chromium, Cr (VI), ion adsorption ability of oyster shell samples collected from two sea regions in Vietnam (Phu Yen province and Quang Ninh province) was investigated and compared. The oyster shell samples were calcined at different temperatures and denatured by using ethylenediaminetetraacetic acid (EDTA). The Cr (VI) ion adsorption ability of the prismatic (PP) and nacreous (NP) shell layers of oysters was also evaluated. The characteristics of oyster shell samples before and after treatment were determined by using analysis methods including XRD, IR, BET, UV-Vis, and FESEM. The Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich models and fit statistic equations were used to study the adsorption isotherms of Cr (VI) ion adsorption by oyster shells. The Cr (VI) ions adsorption kinetic has been set up using four reaction models consisting of first-order, pseudo-first-order, second-order, and pseudo-second-order reaction models. Effects of experimental factors on the Cr (VI) ion adsorption process using oyster shells were also investigated and discussed in this work.

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Adsorption of Dye from Wastewater onto ZnO Nanoparticles-Loaded Zeolite: Kinetic, Thermodynamic and Isotherm Studies

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2018-1342 ◽

2020 ◽

Vol 234 (2) ◽

pp. 255-278

Author(s):

Ahmed Samer Elfeky ◽

Hanan Farouk Youssef ◽

Ahmed Shafek Elzaref

Keyword(s):

Removal Efficiency ◽

Kinetic Studies ◽

Second Order ◽

Exchange Property ◽

X Ray Diffraction ◽

Solution Ph ◽

X Ray ◽

Best Fitting ◽

Pseudo Second Order ◽

Adsorption Desorption

AbstractThe adsorption process of methylene blue (MB) and its removal from aqueous solution at initial pollutant concentration range of 1–7 ppm was investigated. Zeolite-A (Z) and its ZnO-loaded species (Z/ZnO) were prepared via microwave technique from natural resource and applied for dye removal. The loading of ZnO was governed by the cation exchange property of zeolite, followed by calcination. Experimentally, Z and Z/ZnO were tested using X-ray Diffraction (XRD), Fourier-Transform Infrared (FTIR), Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDX) and N2 adsorption-desorption. The examined parameters such as concentration of dye, contact time, ZnO dose and solution pH were traversed. Three isothermal models were analyzed. Kinetic studies indicated that, the adsorption of MB matched with pseudo-second order model. The maximum removal efficiency at pH 3, increased from 67.8% for Z to 94.8% for Z/ZnO modified with 3% ZnO loads (Z/ZnO(3%)). Parameters such as ΔH, ΔS, ΔG, S* and Ea were thermodynamically calculated. Langmiur isotherm and pseudo-second order models were the best fitting for the obtained data. The results indicated that, the adsorption of MB dye is spontaneous and endothermic, the removal efficiency is favored by increasing the temperature. ZnO-zeolite has much higher adsorption capacity for eliminating MB dye than that of the un-loaded zeolite.

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