Lead (II) Pollution Enhances the Binding of Transgenic Toxin in Brown and Red Soils: Equilibrium and Kinetics

2013 ◽  
Vol 11 (1) ◽  
pp. 501-509
Author(s):  
Xueyong Zhou ◽  
Huifen Liu ◽  
Xianzhi Lu ◽  
Lili Shi ◽  
Jianchao Hao
Keyword(s):  
Genetically Modified Crops ◽  
Red Soil ◽  
Second Order ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Free Energy Of Adsorption ◽  
Intraparticle Diffusion Model ◽  
Equilibrium And Kinetics ◽  
Equilibrium Data ◽  
Pseudo Second Order

Abstract Genetically modified crops, which produce insecticidal toxins from Bacillus thuringiensis (Bt), release the toxins into soils. Although the phenomena of persistence and degradation of Bt toxins have been documented, the effect of heavy metals on the fate of these toxins in soil has not yet been elucidated. The effect of Pb(II) on the adsorption behaviors of Bt toxin in brown and red soil was investigated. With the increase of Pb(II) concentration, the adsorption of Bt toxin in brown and red soil increased. The Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherm models gave better fitting to the experimental equilibrium data. Values of KL, KF and n increased but RL decreased with the increase of Pb(II) concentration, showing that the Pb(II) promoted the adsorption of Bt toxin in soils. The mean free energy of adsorption (E) ranged from 10.43 to 16.44 kJ mol−1 may correspond to a chemical ion-exchange mechanism. Three kinds of kinetic models, the pseudo-first-order, pseudo-second-order and intraparticle diffusion model, were used to test the experimental data. The results showed that the adsorption of Bt toxin by brown and red soil followed the pseudo-second-order kinetic model. The addition of Pb(II) during the adsorption led to a decrease of the desorption of Bt toxin from soils, indicating that the residual risk of Bt toxin may become larger if soil is polluted by lead.

scholarly journals Dye removal from artificial wastewater using heterogeneous bio-fenton system

2017 ◽  
Vol 23 (4) ◽  
pp. 447-456
Author(s):  
Rahim Shojaat ◽  
Afzal Karimi ◽  
Naghi Saadatjoo ◽  
Soheil Aber
Keyword(s):  
Kinetic Models ◽  
Calcium Alginate ◽  
Correlation Coefficients ◽  
Second Order ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Initial Ph ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Fenton System

In the present study, GOx/MnFe2O4/calcium alginate nano-composite was prepared by the trapping enzyme/nanoparticles in calcium alginate. The prepared absorbent was applied for decolorization of artificial dye wastewater of acid red 14 (AR14) by heterogeneous bio-Fenton system. Kinetic and isotherm studies were carried out. The decolorization of acid red 14 followed the Michaelis- Menten, pseudo-first order and pseudo-second order kinetic models. Good correlation coefficients were obtained by fitting the experimental data to Michaelis- Menten and pseudo-second order kinetic models. The adsorption isotherms were described by Langmuir, Freundlich and Temkin isotherms. Among the three isotherm models, the Freundlich model was fitted with the equilibrium data obtained from adsorption of AR14 onto MnFe2O4/calcium alginate; while Temkin isotherm gave the best correlation for adsorption on MnFe2O4 nanoparticles. The effect of various parameters such as initial pH of solution, initial dye concentration, and contact time on the adsorption of AR14 on MnFe2O4 and MnFe2O4/ /calcium alginate as well as dye enzymatic decomposition was studied. The decolorization of AR14 with initial concentration of 10 mg.L?1 by using GOx/ /MnFe2O4/calcium alginate was 60.17%.

scholarly journals Application of immobilized waste brewery yeast cells for Cd2+ removal: Equilibrium and kinetics

2011 ◽  
Vol 76 (3) ◽  
pp. 363-373 ◽  
Author(s):  
Szende Tonk ◽  
Andrada Măicăneanu ◽  
Cerasella Indolean ◽  
Silvia Burca ◽  
Cornelia Majdik
Keyword(s):  
Correlation Coefficients ◽  
Alginate Beads ◽  
Second Order ◽  
Yeast Cells ◽  
Order Kinetic ◽  
Waste Biomass ◽  
Biosorption Process ◽  
Equilibrium And Kinetics ◽  
Equilibrium Data ◽  
Pseudo Second Order

In this investigation, the removal of Cd2+ ions by a brewery waste biomass in immobilized (Ca-alginate beads) form was studied. The removal process was conducted at room temperature under batch conditions (magnetic stirring) using different initial cadmium concentrations. The equilibrium of biosorption was reached in 150 minutes for all employed initial concentrations. The maximum biosorption capacity was calculated to be 5.96 mg Cd2+ g-1 yeast for an initial Cd2+ concentration of 169 mg L-1. Langmuir and Freundlich adsorption isotherms were used to correlate the equilibrium adsorption data. Based on the correlation coefficients, it was concluded that the Langmuir isotherm is more suitable for describing the equilibrium data of cadmium biosorption. In addition, first and pseudo-second order kinetic models were applied to describe the biosorption process. The kinetic parameters for the pseudo-second order kinetics were determined.

scholarly journals Equilibrium and kinetics studies for the adsorption of Ni2+ and Fe3+ ions from aqueous solution by graphene oxide

2017 ◽  
Vol 19 (3) ◽  
pp. 120-129 ◽  
Author(s):  
Wojciech Konicki ◽  
Małgorzata Aleksandrzak ◽  
Ewa Mijowska
Keyword(s):  
Graphene Oxide ◽  
Kinetic Model ◽  
Metal Ion ◽  
Second Order ◽  
Ion Concentration ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Intraparticle Diffusion Model ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Abstract In this study, the adsorption of Ni2+ and Fe3+ metal ions from aqueous solutions onto graphene oxide (GO) have been explored. The effects of various experimental factors such as pH of the solution, initial metal ion concentration and temperature were evaluated. The kinetic, equilibrium and thermodynamic studies were also investigated. The adsorption rate data were analyzed using the pseudo-first-order kinetic model, the pseudo-second-order kinetic model and the intraparticle diffusion model. Kinetic studies indicate that the adsorption of both ions follows the pseudo-second-order kinetics. The isotherms of adsorption data were analyzed by adsorption isotherm models such as Langmuir and Freundlich. Equilibrium data fitted well with the Langmuir model. The maximum adsorption capacities of Ni2+ and Fe3+ onto GO were 35.6 and 27.3 mg g−1, respectively. In addition, various thermodynamic parameters, such as enthalpy (ΔHO), entropy (ΔSO) and Gibbs free energy (ΔGO), were calculated.

Equilibrium and Kinetic Modeling on Biosorption of Reactive Red 2 Using Tamarindus indica Fruit Hulls

2008 ◽  
Vol 3 (2) ◽  
Author(s):  
S. Renganathan ◽  
M. Seenuvasan ◽  
S. Selvaraj ◽  
P. Gautam ◽  
M. Velan
Keyword(s):  
Second Order ◽  
Isotherm Model ◽  
Rate Equations ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Tamarindus Indica ◽  
Order Rate ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Reactive Red 2

Biosorption of Reactive Red 2 dye, from an aqueous solution was evaluated using Tamarindus indica fruit hulls in a batch system. The influence of pH (1-6), temperature (20-30°C) and initial dye concentration (20 to 120 mg/L) on the biosorption process was studied. Maximum biosorption was observed at initial pH of 2.0, temperature of 30°C and at the initial dye concentration of 120 mg/L. Equilibrium data were analysed for Langmuir, Freundlich and generalized isotherm model. The equilibrium data were found to fit very well with Freundlich isotherm model when compared to all other isotherm models studied in the present investigation. Batch biosorption kinetics was studied with different initial dye concentrations and rate of biosorption was determined using pseudo first and pseudo second order rate equations. From the result it was observed that pseudo second order rate expression fit the experimental data well for Reactive Red 2 when compared to a pseudo first order kinetic model.

scholarly journals Biosynthesis and Characterization of Iron Nanoparticles for Effective Adsorption of Cr(VI)

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Emel Simla Önal ◽  
Tolga Yatkın ◽  
Tural Aslanov ◽  
Memduha Ergüt ◽  
Ayla Özer
Keyword(s):  
Iron Nanoparticles ◽  
Second Order ◽  
Solution Temperature ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Wide Range ◽  
Initial Ph ◽  
Equilibrium Data ◽  
Pseudo Second Order

In this study, iron nanoparticles (FeNPs) were synthesized via a green method using loquat (Eriobotrya japonica) leaves aqueous extract as a renewable reducing agent. The synthesized FeNPs were characterized by DLS, XRD, FT-IR, SEM/EDX, and TEM analysis, and then, they were used as an adsorbent for Cr(VI) removal from aqueous solutions. Batch adsorption experiments were carried out to investigate the optimum adsorption parameters such as the initial pH of the solution, temperature, initial Cr(VI) concentration, and adsorbent concentration. The optimum adsorption conditions were determined as initial pH 3.0, temperature 45°C, and adsorbent concentration 1 g/L. Also, a linear increase was observed in adsorbed Cr(VI) amounts with the increasing initial Cr(VI) concentrations. The biosynthesized FeNPs showed the high removal levels higher than 90% for Cr(VI) adsorption at a wide range of initial Cr(VI) concentrations (50–500 mg/L). The experimental equilibrium data were modelled with Langmuir and Freundlich isotherm models, and it was found that experimental equilibrium data could be well described by the Langmuir isotherm model. The maximum monolayer coverage capacity of FeNPs for Cr(VI) adsorption was found to be 312.5 mg/g. The pseudo-first-order and the pseudo-second-order kinetic models were applied to the experimental adsorption data, and it was concluded that the data were defined as the best agreement with the pseudo-second-order kinetic model. Weber–Morris model was used to investigate the effect of mass transfer on the adsorption of Cr(VI) onto FeNPs; it was observed that both the film (boundary layer) and intraparticle diffusion affected the studied adsorption process. The thermodynamic studies suggested that Cr(VI) adsorption onto FeNPs was endothermic and nonspontaneous, and the positive ΔS value indicated increased disorder at the solid-solution interface during the adsorption.

scholarly journals Removal of Disperse Blue 56 and Disperse Red 135 dyes from aqueous dispersions by modified montmorillonite nanoclay

2017 ◽  
Vol 23 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Javad Ahmadishoar ◽  
Hajir Bahrami ◽  
Barahman Movassagh ◽  
Hosein Amirshahi ◽  
Mokhtar Arami
Keyword(s):  
Dye Adsorption ◽  
Freundlich Isotherm ◽  
Intraparticle Diffusion ◽  
Second Order ◽  
Isotherm Models ◽  
Disperse Dyes ◽  
Order Kinetic ◽  
Intraparticle Diffusion Model ◽  
Modified Montmorillonite ◽  
Pseudo Second Order

In this study modified montmorillonite was used as an adsorbent for the removal of two selected disperse dyes i.e., Disperse Blue 56 (DB) and Disperse Red 135 (DR) from dye dispersions. The adsorption equilibrium data of dyes adsorption were investigated by using Nernst, Freundlich and Langmuir isotherm models. The adsorption kinetics was analyzed by using different models including pseudo-first-order, pseudo-second-order, Elovich and Intraparticle diffusion model. The Freundlich isotherm was found to be the most appropriate model for describing the sorption of the dyes on modified nanoclay. The best fit to the experimental results was obtained by using the pseudo-second-order kinetic equation, which satisfactorily described the process of dye adsorption. Although different kinetic models may control the rate of the adsorption process, the results indicated that the main rate limiting step was the intraparticle diffusion. The results showed that the proposed modified montmorillonite could be used as an effective adsorbent for the removal of disperse dyes even from highly concentrated dispersions.

scholarly journals Kinetic of Phenol Adsorption by Mesoporous MCM-41 Nanoparticles

2019 ◽  
Vol 8 (12S) ◽  
pp. 316-323 ◽  
Keyword(s):  
Kinetic Equations ◽  
Sem Analysis ◽  
Second Order ◽  
Isotherm Models ◽  
Potential Candidate ◽  
Order Kinetic ◽  
Intraparticle Diffusion Model ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Mcm 41

In the present study application of MCM-41 for removal of phenol was investigated. MCM-41nano-adsorbent was synthesized and characterized by FTIR, XRD and SEM analysis. Adsorption isotherm experiment was performed in batch shake flask. The experimental data were analyzed using various isotherm models. Result revealsthat,Langmuir isotherm model fitted the data very well for the removal of phenol by the MCM-41 adsorbents. The calculated dimensionless separation factor, RL indicates that the adsorption of phenol onto MCM-41 was favorable. Pseudo-first order, pseudo-second order kinetic equations and intraparticle diffusion model were applied to analyze the adsorption kinetics of the MCM-41 at different initial phenol concentrations. It was found that the adsorption of phenol on to the MCM-41 follows the pseudo-second order kinetic. At an initial phenol concentration of 130 mgl-1, more than 99% phenol, 93% COD along with 96% of toxicity removal were achieved. Thus, the synthesized mesoporous MCM-41 proved to be a potential candidate for removal of phenol from industrial wastewater.

Adsorption Characteristics of Phenol in Aqueous Solution by Pinus massoniana Biochar

2013 ◽  
Vol 295-298 ◽  
pp. 1154-1160 ◽  
Author(s):  
Guo Zhi Deng ◽  
Xue Yuan Wang ◽  
Xian Yang Shi ◽  
Qian Qian Hong
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Pinus Massoniana ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Salt Ions ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.

Studies of Chromium Removal from Tannery Effluents by Dead Streptomyces Rimosus

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Mohamed Nasser Sahmoune ◽  
Krim Louhab ◽  
Aissa Boukhiar
Keyword(s):  
Fractional Power ◽  
Kinetic Studies ◽  
Second Order ◽  
Order Kinetic ◽  
Streptomyces Rimosus ◽  
Tannery Effluents ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Ph Range

Dead streptomyces rimosus was found to be an effective biosorbent for the removal of chromium from industrial tanning effluents. A sorption level of 65 mg/g was observed at pH 4.8 while the precipitation effect augmented this value at a higher pH range. Chromium desorption increased with decreasing desorption agents pH (including HCl and H2SO4) to a maximum value of 95% at approximately zero pH. The biosorption data of trivalent chromium by streptomyces rimosus has been used for kinetic studies based on fractional power, Elovich, pseudo-first order and pseudo-second order rate expressions. The time-dependent Cr (III) biosorption data were well-described by a pseudo-second-order kinetic model. The intraparticle diffusion is not the rate-limiting step for the whole reaction. It was found that the biosorption equilibrium data fit well with the Langmuir model.

scholarly journals Comparison of adsorptions by rice hull and Lewatit TP 214 of platinum in chloride solution

2013 ◽  
Vol 78 (6) ◽  
pp. 811-826 ◽  
Author(s):  
M.H. Morcali ◽  
B. Zeytuncu ◽  
O. Yucel
Keyword(s):  
Waste Product ◽  
Second Order ◽  
Attenuated Total Reflection ◽  
Rate Equations ◽  
Rice Hull ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Biomass Waste ◽  
Equilibrium Data ◽  
Pseudo Second Order

Rice hull, a biomass waste product, and Lewatit TP 214, a thiosemicarbazide sorbent, were investigated as adsorbents for the adsorption of platinum (IV) ions from synthetically prepared dilute chloroplatinic acid solutions. The rice hull was characterized by Attenuated Total Reflection-Fourier transform infrared spectroscopy (ATR-FTIR). The effects of the different adsorption parameters, sorbent dosage, contact time, temperature and pH of solution on adsorption percentage were studied in detail on a batch sorption. The adsorption equilibrium data were best fitted with the Langmuir isotherm model. The maximum monolayer adsorption capacities, Qmax, at 25?C were found to be 42.02 and 33.22 mg g-1 for the rice hull and Lewatit TP 214, respectively. Thermodynamic calculations using the measured ?H?, ?S? and ?G? values indicate that the adsorption process was spontaneous and exothermic. The pseudo-first-order and pseudo-second-order rate equations were investigated; the adsorption of platinum ions for both sorbents was found to be described by the pseudo-second-order kinetic model. The kinetic rate, k2, using 30 mg sorbent at 25?C was found to be 0.0289 and 0.0039 g min-1 mg-1 for the rice hull and Lewatit TP 214, respectively. The results indicated that the rice hull can be effectively used for the removal of platinum from aqueous solution.

Sign in / Sign up

Export Citation Format

Share Document