scholarly journals The Influence of the Chemical Structures of Chitosan and Acid Dye on the Adsorption Process

2012 ◽  
Vol 9 (4) ◽  
pp. 2415-2423
Author(s):  
Hayet Ben Ali ◽  
Salma Besbes Hentati ◽  
Salem S. Al-Deyab ◽  
Mohamed Rzaigui ◽  
M'henni Mohamed Farouk
Keyword(s):  
Adsorption Process ◽  
Order Kinetic ◽  
Chemical Structures ◽  
Enthalpy Changes ◽  
Adsorption Processes ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Rate Limiting ◽  
Best Fit ◽  
Efficient Adsorbent

The objective of this paper is the study of the influence of the chemical structures of adsorbent and adsorbate on the adsorption process. By using of crab shell chitosan (CC) and deep-pink shrimp chitosan (CP) for removal of acid 183 and AR114 from aqueous solutions, it is shown that CP, which corresponds to the highest molecular weight, is the most efficient adsorbent material. In addition, the best extent of decolorization is obtained for AR 183 that is the smallest molecule. Langmuir model represents the best fit of the experimental data, indicating monolayer coverage of chitosan outer surface. Pseudo-second order kinetic model describes accurately the adsorption processes, suggesting chemical rate limiting steps. The positive values of the enthalpy changes indicated endothermic attachment of dyes to the biomaterials. CP/AR183 system corresponds to the most energetically favorable phenomenon. Besides, desorption of AR from chitosan was found to be very low in acidic aqueous medium for all couples.

scholarly journals Removal of Malachite Green using Green Synthesized α-MnO2 nanoparticles: Kinetics, Intraparticle Diffusion and Isotherm

2019 ◽  
Vol 9 (1) ◽  
pp. 5255-5258
Keyword(s):  
Malachite Green ◽  
Adsorption Process ◽  
Cost Effective ◽  
Intraparticle Diffusion ◽  
Order Kinetic ◽  
Environment Friendly ◽  
Mno2 Nanoparticles ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Best Fit

This study helps to understand the adsorption of Malachite Green (MG) on α-MnO2 nanoparticles which was green synthesized using sugarcane juice. Different parameters including pH of solution, dosage of adsorbent, concentration of pollutant and time for adsorption process was studied to conclude the efficacy of the process using the adsorbent. The isotherm and kinetics for adsorption of MG concluded that Langmiur isotherm and pseudo second order kinetic model yields the best fit. The maximum monolayer sorption according to Langmiur was found to be 300.03 mg/g. So, α-MnO2 nanoparticles prove to be a cost effective, environment friendly and easily available 3D adsorbent.

Effects of tall fescue biochar on the adsorption behavior of desethyl-atrazine in different types of soil

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 3575-3595
Author(s):  
Wanting Li ◽  
Ruifeng Shan ◽  
Yuna Fan ◽  
Xiaoyin Sun
Keyword(s):  
Tall Fescue ◽  
Adsorption Process ◽  
Exothermic Reaction ◽  
Equilibrium Concentration ◽  
Black Soil ◽  
Adsorption Behavior ◽  
Order Kinetic ◽  
Isothermal Adsorption ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Desethyl-atrazine (DEA) is a metabolite of atrazine that exerts a considerable influence on the environment. In this study, tall fescue biochar was prepared by pyrolysis at 500 °C, and batch experiments were conducted to explore its effect on the adsorption behavior of DEA in red soil, brown soil, and black soil. The addition of biochar increased the equilibrium amount of DEA adsorption for the three soil types. A pseudo-second-order kinetic model most closely fit the DEA adsorption kinetics of the three soils with and without biochar, with a determination coefficient (R2) of 0.962 to 0.999. The isothermal DEA adsorption process of soils with and without biochar was optimally described by the Freundlich and Langmuir isothermal adsorption models with R2 values of 0.98 and above. The DEA adsorption process in the pristine soil involved an exothermic reaction, which became an endothermic reaction after the addition of biochar. Partitioning was dominant throughout the entire DEA adsorption process of the three pristine soils. Conversely, in soils with biochar, surface adsorption represented a greater contribution toward DEA adsorption under conditions of low equilibrium concentration. The overall results revealed that the tall fescue biochar was an effective adsorbent for DEA polluted soil.

scholarly journals Removal of Lead(II) from Synthetic Wastewater by Lavandula pubescens Decne Biosorbent: Insight into Composition–Adsorption Relationship

2020 ◽  
Vol 10 (21) ◽  
pp. 7450
Author(s):  
Ali Q. Alorabi ◽  
Fahad A. Alharthi ◽  
Mohamed Azizi ◽  
Nabil Al-Zaqri ◽  
Adel El-Marghany ◽  
...  
Keyword(s):  
Ion Concentration ◽  
Wild Plant ◽  
Synthetic Wastewater ◽  
Gas Chromatography Mass Spectrometry ◽  
Gas Liquid Chromatography ◽  
Order Kinetic ◽  
Freundlich Model ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Best Fit

In this work, the widely-abundant, cheap, wild plant Lavandula pubescens Decne was evaluated as an adsorbent for removing Pb(II) ions from wastewater. The chemical composition of the plant was partially isolated and characterized by the corresponding techniques, including gas chromatography–mass spectrometry, gas liquid chromatography, and FTIR spectroscopy. The adsorption capacity of the dried plant material for Pb(II) ions increased with increasing contact time, initial ion concentration, and temperature, while it decreased with increasing adsorbent dosage. The optimum condition for Pb(II) adsorption was determined as 550 mg/L initial metal concentration, pH ≤ 7, and 90 min of contact. The best fit for Pb(II) adsorption isotherms was the linear form of the Freundlich model; however, the maximum capacity indicated by Langmuir was 91.32 mg/g. The experimental data fit better the pseudo-second-order kinetic model (R2 = 0.969), suggesting chemisorption process. Thermodynamic data revealed an endothermic, nonspontaneous, and adsorption process favored at higher concentrations.

scholarly journals Construction of Novel Polymerizable Ionic Liquid Microemulsions and the In Situ Synthesis of Poly(Ionic Liquid) Adsorbents

Nanomaterials ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 454 ◽  
Author(s):  
Aili Wang ◽  
Shuhui Li ◽  
Hou Chen ◽  
Ying Liu ◽  
Xiong Peng
Keyword(s):  
Ionic Liquid ◽  
Adsorption Process ◽  
Freundlich Isotherm ◽  
In Situ Synthesis ◽  
Scattering Data ◽  
Order Kinetic ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Poly Ionic Liquid

This paper reports the successful construction of novel polymerizable ionic liquid microemulsions and the in situ synthesis of poly(ionic liquid) adsorbents for the removal of Zn2+ from aqueous solution. Dynamic light-scattering data were used to confirm the polymerization media and to illustrate the effect of the crosslinker dosage on the droplet size of the microemulsion. FTIR and thermal analysis were employed to confirm the successful preparation of the designed polymers and characterize their thermostability and glass transition-temperature value. The optimization of the adsorption process indicates that the initial concentration of Zn2+, pH, adsorbent dosage and contact time affected the adsorption performance of poly(ionic liquid)s toward Zn2+. Furthermore, our research revealed that the adsorption process can be effectively described by the pseudo second-order kinetic model and the Freundlich isotherm model.

Biodecolorization of Basic Violet 03 Using Biochar Derived from Agricultural Wastes: Isotherm and Kinetics

2020 ◽  
Vol 14 (3) ◽  
pp. 316-326 ◽  
Author(s):  
Josephraj Jegan ◽  
Saravanan Praveen ◽  
Thillainayagam Bhagavathi Pushpa ◽  
Ravindran Gokulan
Keyword(s):  
Binding Capacity ◽  
Maximum Yield ◽  
Agricultural Wastes ◽  
Order Kinetic ◽  
Optimum Conditions ◽  
Batch Mode ◽  
Before And After ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Best Fit

In the present study, bioremediation of Basic Violet 03 is examined using biochar derived from agricultural wastes. The pyrolytic studies revealed that ideal temperature for maximum yield of biochar derived from Coconut Shell (CSB), Ground nut Shell (GnSB) and Rice Husk (RHB) was obtained as 400 °C, 350 °C and 300 °C respectively. Further from the batch mode of operations, it was concluded that the optimum conditions of biochar dose, pH, temperature and initial concentration are 4 g/L, 8, 40 °C and 75 mg/L with a maximum uptake of 15.79 mg/g, 17.28 mg/g, and 12.64 mg/g for CSB, GnSB and RHB. The adsorption isotherm studies concluded that the three-parameter Sips model was obtained to be the best fit with a maximum correlation coefficient (R2) of 0.9937, 0.9935 and 0.9965. The pseudo second order kinetic model was found to well represent the experimental kinetic data. The characterization results of biochar through SEM, EDX and FTIR revealed that there was a strong binding capacity of adsorbent was observed before and after adsorption process. The promising results concluded that biochar derived from agricultural wastes can potentially be utilized for the removal of cationic dyes.

Removal of fluoride from aqueous solution by adsorption onto Kanuma mud

2010 ◽  
Vol 62 (8) ◽  
pp. 1888-1897 ◽  
Author(s):  
Nan Chen ◽  
Zhenya Zhang ◽  
Chuanping Feng ◽  
Miao Li ◽  
Rongzhi Chen ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Fluoride Concentration ◽  
Freundlich Isotherm ◽  
Order Kinetic ◽  
Solution Ph ◽  
Intra Particle Diffusion ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Solid Liquid Interface ◽  
Solid Liquid

Kanuma mud, a geomaterial, is used as an adsorbent for the removal of fluoride from water. The influences of contact time, solution pH, adsorbent dosage, initial fluoride concentration and co-existing ions were investigated by batch equilibration studies. The rate of adsorption was rapid with equilibrium being attained after about 2 h, and the maximum removal of fluoride was obtained at pH 5.0–8.0. The Freundlich isotherm model was found to represent the measured adsorption data well. The negative value of the thermodynamic parameter ΔG suggests the adsorption of fluoride by Kanuma mud was spontaneous, the endothermic nature of adsorption was confirmed by the positive ΔH value. The negative ΔS value for adsorbent denoted decreased randomness at the solid/liquid interface. The adsorption process using Kanuma mud followed the pseudo-second-order kinetic model. Fluoride uptake by the Kanuma mud was a complex process and intra-particle diffusion played a major role in the adsorption process. It was found that adsorbed fluoride could be easily desorbed by washing the adsorbent with a solution of pH 12. This indicates the material could be easily recycled.

scholarly journals Preparation and Characterization of a Novel Amidoxime-Modified Polyacrylonitrile/Fly Ash Composite Adsorbent and Its Application to Metal Wastewater Treatment

2022 ◽  
Vol 19 (2) ◽  
pp. 856
Author(s):  
Yan Sun ◽  
Xiaojun Song ◽  
Jing Ma ◽  
Haochen Yu ◽  
Gangjun Liu ◽  
...  
Keyword(s):  
Fly Ash ◽  
Adsorption Process ◽  
Single Layer ◽  
Nitrogen Adsorption ◽  
Order Kinetic ◽  
X Ray Diffraction ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
High Degree

The polyacrylonitrile/fly ash composite was synthesized through solution polymerization and was modified with NH2OH·HCl. The amidoxime-modified polyacrylonitrile/fly ash composite demonstrated excellent adsorption capacity for Zn2+ in an aqueous medium. Fourier transform-Infrared spectroscopy, thermogravimetric analysis, nitrogen adsorption, X-ray diffraction, and scanning electron microscopy were used to characterize the prepared materials. The results showed that the resulting amidoxime-modified polyacrylonitrile/fly ash composite was able to effectively remove Zn2+ at pH 4–6. Adsorption of Zn2+ was hindered by the coexisting cations. The adsorption kinetics of Zn2+ by Zn2+ followed the pseudo-second order kinetic model. The adsorption process also satisfactorily fit the Langmuir model, and the adsorption process was mainly single layer. The Gibbs free energy ΔG0, ΔH0, and ΔS0 were negative, indicating the adsorption was a spontaneous, exothermic, and high degree of order in solution system.

scholarly journals Microstructural and Equilibrium Adsorption Study of the System of Waste Foundry Molding Sand/Cu (II) Ions

2016 ◽  
Vol 61 (4) ◽  
pp. 1805-1812
Author(s):  
A. Strkalj ◽  
Z. Glavas ◽  
L. Slokar
Keyword(s):  
Experimental Data ◽  
Adsorption Process ◽  
Order Kinetic ◽  
Molding Sand ◽  
Adsorption Study ◽  
Eds Analysis ◽  
Adsorption Capacities ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Casting Production

Abstract This paper deals with the waste foundry molding sand which originally comes from the casting production. Adsorption of Cu (II) ions on the waste foundry molding sand was studied. Experimental data were processed using adsorption isotherms. Obtained results show that the experimental data are best described by the Langmuir isotherm. The following adsorption capacities are obtained: 7.153 mg/g to 293 K, 8.403 mg/g at 333 K and 9.208 mg/g at 343 K. The kinetics and thermodynamics of the process were analysed. The obtained results indicate that the adsorption process takes place according to the pseudo second order kinetic model with the following constants: 0.438 g/mg min at 293 K, 0.550 g/mg min at 333 K and 1.872 g/mg min at 343 K. The following values of ΔG° were obtained: − 95.49 J/mol at 293 K, − 736.99 J/mol at 333 K and − 1183.46 J/mol at 343 K. The value of ΔH° is − 4.16 kJ/mol and the value of ΔS° is 15.17 J/molK. These results were confirmed by microscopic examinations. The results indicate that the adsorption process of Cu (II) ions on waste foundry molding sand is possible. Results of microscopic examinations show the homogeneity of the surface, which is proof of the chemisorption. Cu (II) ions on the surface of the waste foundry molding sand were detected after adsorption by EDS analysis, which proves the existence of the adsorption process.

scholarly journals Removal of COD from Groundwater in and Around Industrial Areas - Using Activated Carbon Powder Prepared by Groundnut Foliage and Groundnut Husk

2021 ◽  
Vol 37 (4) ◽  
pp. 922-927
Author(s):  
A. Kistan ◽  
V. Kanchana ◽  
N. K. Geetha ◽  
G. Infant Sujitha
Keyword(s):  
Activated Carbon ◽  
Kinetic Model ◽  
Adsorption Process ◽  
Oxygen Demand ◽  
Carbon Powder ◽  
Order Kinetic ◽  
Industrial Areas ◽  
Sem Image ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The following study explains that the adsorption efficiency of activated carbon used by Groundnut foliage and groundnut husk for the deportation of COD (Chemical Oxygen demand) from groundwater collected from in and around industrial areas of Vellore district was investigated with different activating conditions (Activating agent- KOH, ZnCl2 and H3PO4; Impregnation ratio-1:1,1:2,1:2; and activation temeperture-500-700°C. The activated carbon prepared based on optimized condition has well-developed pore structure and functional groups which is confirmed from SEM image and FTIR analysis respectively. The adsorption equilibrium was reached in 240 min with the isotherm data fitted well in both the model such as Langmuir model and Freundlich’s model indicating chemisorption’s adsorption for the activated carbon. Moreover, the adsorption process was exothermic accompanied by a decrease in irregularity. Furthermore, the adsorption kinetic study indicated that the adsorption process of the prepared sample follows the pseudo-second-order kinetic model compare to the pseudo-first -order kinetic model

Adsorption of Cu(II), Ni(II) and Zn(II) ions by nano kaolinite: Thermodynamics and kinetics studies

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Metal Ions ◽  
Metal Ion ◽  
Adsorption Process ◽  
Ion Concentration ◽  
Order Kinetic ◽  
Adsorption Data ◽  
Order Kinetic Model ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Ft Ir

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.

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