scholarly journals Adsorption kinetic, equilibrium and thermodynamic investigations of Zn(II) and Ni(II) ions removal by poly(azomethinethioamide) resin with pendent chlorobenzylidine ring

2015 ◽  
Vol 17 (3) ◽  
pp. 100-109 ◽  
Author(s):  
P. Senthil Kumar ◽  
H. Ethiraj ◽  
Anita Venkat ◽  
N. Deepika ◽  
S. Nivedha ◽  
...  

Abstract This paper reports the application of poly(azomethinethioamide) (PATA) resin having the pendent chlorobenzylidine ring for the removal of heavy metal ions such as Zn(II) and Ni(II) ions from the aqueous solutions by adsorption technology. Kinetic, equilibrium and thermodynamic models for Zn(II) and Ni(II) ions adsorption were applied by considering the effect of contact time, initial metal ion concentration and temperature data, respectively. The adsorption influencing parameters for the maximum removal of metal ions were optimized. Adsorption kinetic results followed the pseudo-second order kinetic model based on the correlation coefficient (R2) values and closed approach of experimental and calculated equilibrium adsorption capacity values. The removal mechanism of metal ions by PATA was explained with the Boyd kinetic model, Weber and Morris intraparticle diffusion model and Shrinking Core Model (SCM). Adsorption equilibrium results followed the Freundlich model based on the R2 values and error functions. The maximum monolayer adsorption capacity of PATA for Zn(II) and Ni(II) ions removal were found to be 105.4 mg/g and 97.3 mg/g, respectively. Thermodynamic study showed the adsorption process was feasible, spontaneous, and exothermic in nature.

2017 ◽  
Vol 19 (3) ◽  
pp. 120-129 ◽  
Author(s):  
Wojciech Konicki ◽  
Małgorzata Aleksandrzak ◽  
Ewa Mijowska

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.


2022 ◽  
Vol 0 (0) ◽  
Author(s):  
Md. Nabul Sardar ◽  
Nazia Rahman ◽  
Shahnaz Sultana ◽  
Nirmal Chandra Dafader

Abstract This study focuses on the adsorption of hazardous Cr (III) and Cu (II) ions from aqueous solution by applying modified waste polypropylene (PP) fabric as an adsorbent. Pre-irradiation technique was performed for grafting of sodium styrene sulfonate (SSS) and acrylic acid (AAc) onto the PP fabric. The monomer containing 8% SSS and 16% AAc in water was used. Graft yield at 30 kGy radiation dose was 390% when 4% NaCl was added as additive. The prepared adsorbent was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA) and dynamic mechanical analyzer (DMA). The influences of different parameters including pH, contact time, temperature and initial metal ion concentration were also investigated. The equilibrium adsorption data were better fitted to the Langmuir isotherm model with maximum monolayer adsorption capacity 384.62 mg/g for Cr (III) and 188.68 mg/g for Cu (II) ions. The kinetic data were better explained by pseudo first-order kinetic model having good matching between the experimental and theoretical adsorption capacity. The adsorption process was spontaneous, endothermic and thermodynamically feasible. Furthermore, investigation of desorption of metal ions and reuse of the adsorbent suggesting that the adsorbent is an efficient and alternative material in the removal of Cr (III) and Cu (II) from aqueous media.


2019 ◽  
Author(s):  
Chem Int

An easy route for preparation emulsion of kaolinite (Al2Si2O5.4H2O) from Sweileh sand deposits, west Amman, Jordan by hydrochloric acid under continuous stirring for 4 h at room temperature was performed and nano kaolinite powder was used as an adsorbent for the removal of Cu(II), Zn(II) and Ni(II) ions. Nano kaolinite was characterized by XRD, FT-IR and SEM techniques. Effect of pH, adsorbent dose, initial metal ion concentration, contact time and temperature on adsorption process was examined. The negative values of ΔGo and the positive value of ΔHo revealed that the adsorption process was spontaneous and endothermic. The Langmuir isotherm model fitted well to metal ions adsorption data and the adsorption capacity. The kinetic data provided the best correlation of the adsorption with pseudo-second order kinetic model. In view of promising efficiency, the nano kaolinite can be employed for heavy metal ions adsorption.


Clay Minerals ◽  
2013 ◽  
Vol 48 (5) ◽  
pp. 771-787 ◽  
Author(s):  
A. Bourliva ◽  
K. Michailidis ◽  
C. Sikalidis ◽  
A. Filippidis ◽  
M. Betsiou

AbstractThree bentonite samples (B1, B2, B3) from Milos Island, Greece, were investigated by XRD, AAS, DTA-TG, FTIR and specific surface area measurement techniques. A laboratory batch study has been performed to investigate the adsorption characteristics of lead ions (Pb2+) onto natural bentonite samples. The effect of various physicochemical factors that influence adsorption, such as solution pH (2–6), adsorbent dosage (1–10 g L–1), contact time (20–360 min), and initial metal ion concentration (5–150 mg L–1) was studied. A number of available models like the Lagergren pseudo first-order kinetic model, the pseudo second-order kinetic model and intra-particle diffusion were utilized to evaluate the adsorption kinetics. The adsorption of Pb2+ was modelled with the Langmuir, Freundlich and D-R isotherms. The maximum Pb2+ adsorption capacities for B1, B2 and B3 were 85.47 mg g–1, 73.42 mg g–1 and 48.66 mg g–1, respectively.


Author(s):  
E. S. Isagba ◽  
S. Kadiri ◽  
I. R. Ilaboya

This paper investigated the use of yam peel as a natural adsorbent for the removal of Copper (Cu) and Manganese (Mn) from waste water. The yam peels were thoroughly washed with distilled water, dried, pulverized and carbonized. The carbonized yam peel was then characterized for its particle sizes, moisture content, ash content, volatile matter, Methylene Blue number, Iodine number. The raw yam peels were prepared using the same procedure, but was not carbonized. The adsorption of Mn(II) and Cu(II) ions were investigated using adsorption experiment at room temperature. The effect of contact time, metal ion concentration and dosage were evaluated. The residual concentrations of the metal ions were determined by Atomic Absorption Spectrophotometer (AAS). Experimental data obtained were analyzed using Kinetic models and Isotherms such as Pseudo- First order kinetic models, Pseudo-second order kinetic models, Langmuir isotherms and Freundlich isotherm. The analysis showed that the pseudo-second order kinetic model best described the adsorption of the metal ions; ( Cu; r2 = 0.991 for RYP and r2 = 0.834 for AYP) and (Mn; r2 = 0.958 for RYP and r2 = 0.896 for AYP) and the experimental data best fit the Freundlich model; (Cu; r2 = 0.564 for RYP and r2 = 0.871 for AYP) and (Mn; r2 = 0.685 for RYP and r2 = 0.736 for AYP). Finally, optimum removal efficiencies of 30.54% for Mn(II) and 39.62% for Cu(II) were obtained for AYP at concentrations of 50mg/l and mass dosage of 1.0g, 120 minutes contact time and a pH of 6.8.


2019 ◽  
Vol 9 (4-A) ◽  
pp. 409-414 ◽  
Author(s):  
S. Krishnaveni ◽  
V. Thirumurugan

Pollution is the main problem due to heavy metal discharges from industries .  In this study Ipomoea carnea  (Family:Convolvulaceae) is selected to remove the heavy metal chromium from aqueous chromium solution using biosorbent . The present work focuses to evaluate the effectiveness of low cost absorbent Ipomoea carnea  root powder. Various parameters like pH, biosorbent, dose, contact time and metal ion concentration are investigated using batch studies. A kinetic model study and isotherm model fitting study are studied using Langmuir and Freundlich isotherms. The Thermodyamic parameters ∆G, ∆H and ∆S are also seen. The results reveal that it follows pseudo first order kinetic model and also fit in the Langmuir and Freundlich isotherms. The results are very much encouraging. So, it can be used as low cost biosorbent in controlling the pollution. Keywords: Pollution, Heavy metal, chromium, Ipomoea carnea, Batch adsorption study, Kinetics Langmuir and Freundlich isotherms and Thermodynamic study.


2019 ◽  
Author(s):  
Chem Int

The potential of plantain (Musa paradisiaca) flower to remove Cd(II), Pb(II) and Zn(II) from aqueous solutions has been investigated under different process parameters like pH, contact time, biomass dose and initial metal ion concentration. The optimum pH for the biosorption of each of the metal ions is pH 6. The kinetic data obtained were subjected to four kinetic models, among which the pseudo-second order kinetic model was found to be the best model that describes the biosorption of each of the metal ions. The equilibrium sorption data were fitted into Langmuir, Freundlich, Temkin and D-R isotherms. In each case, the Freundlich isotherm model gave the best fit giving the sorption intensity (n) values of 1.17, 0.91 and 0.90 which indicate favourable sorption of Cd(II), Pb(II) and Zn(II), respectively. The heat of the sorption process was estimated from Temkin Isotherm model and the mean free energy was estimated from D-R isotherm model to be 312.81Jmol-1, 223.61Jmol-1 and 316.55Jmol-1 for Cd(II), Pb(II) and Zn(II), respectively. Thermodynamically, the biosorption of each of the metal ions is endothermic and the order of spontaneity of the biosorption process being Cd(II) > Zn(II) > Pb(II). Similarly, positive change in entropy was observed for each, the order of disorderliness is Cd(II) > Zn(II) = Pb(II).


2019 ◽  
Author(s):  
Chem Int

The equilibrium, kinetics, and thermodynamics of the biosorption of Pb(II), Cd(II) and Zn(II) onto groundnut (Arachis hypogaea) shell were investigated under various physicochemical parameters. Optimisation studies were carried out using batch biosorption studies. The extent of the metal ion biosorption increased with increase in solution pH, initial metal ion concentration, dosage of biosorbent and contact time but decreased with the temperature of the system. The biosorption of each of the metal ions was found to be pH-dependent. Kinetic study showed that the metal ions biosorption process followed the pseudo-second-order kinetic model. The sorption of each metal ion was analysed with Freundlich and Langmuir isotherm models, in each case, the equilibrium data were better represented by Freundlich isotherm model. Thermodynamically, parameters such as standard Gibbs free energy (ΔG˚), standard enthalpy (ΔH˚), standard entropy (ΔS˚) and the activation energy (A) were calculated. The biosorption of each metal ion was spontaneous and the order of spontaneity of the biosorption process being Cd(II) > Zn(II) > Pb(II). Similarly, change in entropy was observed for each and the order of disorder is Cd(II) > Zn(II) > Pb(II).


2020 ◽  
Vol 995 ◽  
pp. 183-188
Author(s):  
Lester Raj Somera ◽  
Ralph Cuazon ◽  
John Kenneth Cruz ◽  
Leslie Joy L. Diaz

Exposure to toxic concentrations of Cu (II) continues to rise as developing countries undergo rapid industrialization. Because of its high solubility in water, improperly disposed copper contaminate our water sources in its aqueous Cu (II) form. A nanofiber membrane composed of iron-modified montmorillonite (Fe-MMt) dispersed in polycaprolactone (PCL) was electrospun for the adsorption of Cu (II) ions. Kinetics and isotherm models were used to study the adsorption behavior of the fabricated membrane. The adsorption capacity of this membrane was observed as a function of increasing contact time and initial Cu (II) ion concentration. Kinetic studies showed that Cu (II) adsorption follows a pseudo-second order kinetic model, while isotherm studies determined the adsorption to be monolayer as described by the Langmuir isotherm. Furthermore, it was observed that the adsorption capacity increases with increasing contact time, and with increasing initial metal ion concentration up to a maximum value of 6.44 mgg-1. Lastly, the Dubinin-Kaganer-Radushkevich isotherm was used to calculate for the sorption energy and determine the type of adsorption. A sorption energy of-5.83 kJmol-1 was obtained, thus the adsorption was classified to be physical.


Author(s):  
Zeynab Karimi ◽  
Reza Khalili ◽  
Mohammad Ali Zazouli

Abstract In this study, polythiophene/Al2O3 (PTh/Al2O3) and polyaniline/Al2O3 (PAn/Al2O3) nanocomposites in the presence of poly(vinyl alcohol) (PVA) as the surfactant were synthesized via in situ chemical oxidative polymerization method in aqueous medium. The synthesized nanocomposites were characterized by Scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) spectroscopy and X-ray diffraction (XRD). Results indicated that the Al2O3 and poly(vinyl alcohol) influenced the properties of synthesized nanocomposites. The aim of this research was to investigate the sorption characteristic of polythiophene and polyaniline nanocomposites for the removal of heavy metal cations including Pb(II), Zn(II) and Cd(II) from aqueous solution. The factors that affected the adsorption equilibrium as well as the removal efficiency of the nanoadsorbents, i.e., contact time, metal ion concentration, pH and adsorption conditions were investigated in detail. From the kinetic results, it was concluded that the pseudo-second-order kinetic model was found to the best at describing the adsorption process for Pb(II), Zn(II) and Cd(II) on PTh-PVA/Al2O3 and PAn-PVA/Al2O3. In addition, thermodynamic analysis suggests the endothermic and spontaneous nature of the present adsorption process with increased entropy on PTh-PVA/Al2O3 and PAn-PVA/Al2O3. The results suggest polythiophene, polyaniline and their nanocomposites have great potential to be used as efficient absorbent for the removal of heavy metal ions from water.


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