scholarly journals Reactive orange 12 dye adsorption onto magnetically separable CaFe2O4 nanoparticles synthesized by simple chemical route: kinetic, isotherm and neural network modeling

2021 ◽  
Author(s):  
Payel Das ◽  
Animesh Debnath
Keyword(s):  
Neural Network ◽  
Experimental Data ◽  
Adsorption Process ◽  
Mean Squared Error ◽  
Dye Adsorption ◽  
Neural Network Modeling ◽  
Order Kinetic ◽  
Solution Ph ◽  
Average Pore ◽  
Reactive Orange

Abstract Industrial wastewaters laden with toxic dyes are required to be treated prior to their disposal in view of their adverse effect on human health and aquatic ecosystem. Thus in this research, CaFe2O4 nanoparticles were prepared and used as adsorbent for elimination of reactive orange 12 dye (RO12) from aqueous medium. The CaFe2O4 nanoparticles exhibit specific surface area of ∼230 m2/g and average pore diameter of ∼2.5 nm. Maximum RO12 removal of 77% was observed at solution pH 2.0 with uptake capacity of 276.92 mg/g. The electrostatic interaction between CaFe2O4 nanoparticles and RO12 was the main driving force behind this adsorption. The kinetic modeling reveal that this adsorption process obeyed the pseudo-second-order kinetic model accurately (R2: 0.988–0.994) indicating the chemisorption behavior. The adsorption experimental data firmly followed the Langmuir isotherm model (R2: 0.997), confirming the monolayer adsorption. Thermodynamic study suggests that the adsorption process is spontaneous (ΔG0 = −8.76 to −3.19 kJ/mol) and exothermic in nature (ΔH0 = –71.86 kJ). A neural network model (optimum topology of 4–7–1) was developed for precise forecasting of RO12 removal (%). The developed model with very high correlation coefficient (0.986) and very low mean squared error (0.00185) was successful for accurate prediction of experimental data.

scholarly journals Removal of Basic Orange 2 dye and Ni2+ from aqueous solutions using alkaline-modified nanoclay

2021 ◽  
Author(s):  
Armin Geroeeyan ◽  
Ali Niazi ◽  
Elaheh Konoz
Keyword(s):  
Experimental Data ◽  
High Efficiency ◽  
Adsorption Process ◽  
Kinetic Equations ◽  
Dye Adsorption ◽  
Second Order ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Diffusion Kinetic ◽  
Pseudo Second Order

Abstract In the present research, the removal of Basic Orange 2 (BO2) dye using alkaline-modified clay nanoparticles was studied. To characterize the adsorbent, XRD, FTIR, FESEM, EDX, BET and BJH analyses were performed. The effect of the variables influencing the dye adsorption process such as adsorbent dose, contact time, pH, stirring rate, temperature, and initial dye concentration was investigated. Furthermore, the high efficiency of Ni2+ removal indicated that it is possible to remove both dye and metal cation under the same optimum conditions. The experimental data were analyzed by Langmuir and Freundlich isotherm models. Fitting the experimental data to Langmuir isotherm indicated that the monolayer adsorption of dye occurred at homogeneous sites. Experimental data were also analyzed with pseudo-first-order, pseudo-second-order, and intra-particle diffusion kinetic equations for kinetic modeling of the dye removal process. The adsorption results indicated that the process follows a pseudo-second-order kinetic model. The thermodynamic parameters of the dye adsorption process such as enthalpy, entropy, and Gibbs free energy changes were calculated and revealed that the adsorption process was spontaneous and endothermic in nature. The results presented the high potential of the modified nanoclay as a cost-effective adsorbent for the removal of BO2 dye and Ni2+ from aqueous medium.

scholarly journals Kinetics, Isotherm and Thermodynamic Studies for Efficient Adsorption of Congo Red Dye from Aqueous Solution onto Novel Cyanoguanidine-Modified Chitosan Adsorbent

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4446
Author(s):  
Nouf F. Al-Harby ◽  
Ebtehal F. Albahly ◽  
Nadia A. Mohamed
Keyword(s):  
Aqueous Solution ◽  
Congo Red ◽  
Adsorption Process ◽  
Ph Value ◽  
Dye Adsorption ◽  
Order Kinetic ◽  
Amino Groups ◽  
Solution Ph ◽  
Intraparticle Diffusion Model ◽  
Modified Chitosan

Novel Cyanoguanidine-modified chitosan (CCs) adsorbent was successfully prepared via a four-step procedure; first by protection of the amino groups of chitosan, second by insertion of epoxide rings, third by opening the latter with cyanoguanidine, and fourth by restoring the amino groups through elimination of the protection. Its structure and morphology were checked using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The adsorption capacity of CCs for Congo Red (CR) dye was studied under various conditions. It decreased significantly with the increase in the solution pH value and dye concentration, while it increased with increasing temperature. The adsorption fitted to the pseudo-second order kinetic model and Elovich model. The intraparticle diffusion model showed that the adsorption involved a multi-step process. The isotherm of CR dye adsorption by CCs conforms to the Langmuir isotherm model, indicating the monolayer nature of adsorption. The maximum monolayer coverage capacity, qmax, was 666.67 mg g−1. Studying the thermodynamic showed that the adsorption was endothermic as illustrated from the positive value of enthalpy (34.49 kJ mol−1). According to the values of ΔG°, the adsorption process was spontaneous at all selected temperatures. The value of ΔS° showed an increase in randomness for the adsorption process. The value of activation energy was 2.47 kJ mol−1. The desorption percentage reached to 58% after 5 cycles. This proved that CCs is an efficient and a promising adsorbent for the removal of CR dye from its aqueous solution.

Melia azedarach Activated Carbon and its novel TiO2 Nanocomposite for Chemisorption and Photodecoloration of Reactive Orange 16: Isotherm and Kinetic Modeling

2020 ◽  
Vol 17 (1) ◽  
pp. 107-119
Author(s):  
Jehanzeb A. Shah ◽  
Tayyab Ashfaq ◽  
Muhammad S. Khan ◽  
Nadia Riaz ◽  
Khizar H. Shah ◽  
...  
Keyword(s):  
Experimental Data ◽  
Activated Carbon ◽  
Batch Reactor ◽  
Dye Adsorption ◽  
Optimal Solution ◽  
Melia Azedarach ◽  
Textile Dye ◽  
Order Kinetic ◽  
Reactive Orange 16 ◽  
Reactive Orange

Background: Bulk generated textile wastewater loaded with dyes is posing a stern threat to aquatic health, especially when dumped without prior treatment. Lignocellulosic waste based activated carbon (AC) and Titania (TiO2) suspension can constitute the emerging technological solution. Objectives: Best lignocellulosic precursor biomass, Melia azedarach (Darek sawdust - DSD), was selected for ortho-phosphoric acid impregnated AC production and novel AC-DSD-TiO2 nanocomposite was developed. AC-DSD and AC-DSD-TiO2 nanocomposites were employed for reactive orange 16 (RO16) dye adsorption in batch and decoloration in photocatalytic reactors, respectively. Methods: Materials were characterized by Scanning electron microscope (SEM), energy dispersion X-ray (EDX) spectroscopy and Fourier transform infrared spectroscopy (FTIR). For AC-DSD production, the raw powdered biomass of DSD impregnated (value = 2) with H3PO4 at room temperature and after shaking, was placed in a muffle furnace at 100°C for 12 h in glass tubes and subsequently carbonized at a high temperature of 400°C for 30 min. Batch reactor parameters for the ACDSD- RO16 system were optimized as a function of contact time, adsorbent dose, temperature, initial dye concentration and pH. For AC-DSD-TiO2 nanocomposite synthesis, AC-DSD and TiO2 paste was dried in the furnace at 90°C and calcined at 300°C and stored in a desiccator. Results: AC-DSD exhibited RO16 adsorption capacity of 92.84 mg/g. The experimental data were best described by Langmuir and Dubinin-Radushkevich isotherms with high R2 of 0.9995 and 0.9895 and closeness of predicted adsorption capacities of 94.15 and 88.58 mg/g respectively. This determines the chemisorption nature for RO16 adsorption onto AC-DSD. The experimental data was well explained by the pseudo-second order kinetic model. Thermodynamic parameters also suggest the endothermic, chemisorption and spontaneous adsorption reaction. Photocatalytic studies of novel AC-DSD-TiO2 revealed the higher Kc = 0.1833 value over Kad= 0.0572. Conclusions: Melia azedarach AC-DSD and its novel AC-DSD-TiO2 nanocomposite prove that these materials could provide an optimal solution for treating textile dye solutions effectively as the good adsorbent and photocatalyst.

scholarly journals Multilayer method for solving a problem of metals rupture under creep conditions

2019 ◽  
Vol 23 (Suppl. 2) ◽  
pp. 575-582 ◽  
Author(s):  
Evgenii Kuznetsov ◽  
Sergey Leonov ◽  
Dmitry Tarkhov ◽  
Alexander Vasilyev
Keyword(s):  
Neural Network ◽  
Experimental Data ◽  
Parameter Identification ◽  
Uniaxial Tension ◽  
Network Modeling ◽  
Identification Problem ◽  
Neural Network Modeling ◽  
Creep Theory ◽  
Parameter Identification Problem ◽  
Kinetic Creep

The paper deals with a parameter identification problem for creep and fracture model. The system of ordinary differential equations of kinetic creep theory is applied for describing this model. As for solving the parameter identification problem, we proposed to use the technique of neural network modeling, as well as the multilayer approach. The procedures of neural network modeling and multilayer approximation constructing application is demonstrated by the example of finding parameters for uniaxial tension model for isotropic steel 45 specimens at creep conditions. The solution corresponding to the obtained parameters agrees well with theoretical strain-damage characteristics, experimental data, and results of other authors.

scholarly journals Preparation and Characterization of Chitosan/Feldspar Biohybrid as an Adsorbent: Optimization of Adsorption Process via Response Surface Modeling

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Maryam Yazdani ◽  
Hajir Bahrami ◽  
Mokhtar Arami
Keyword(s):  
Response Surface ◽  
Adsorption Process ◽  
Dye Adsorption ◽  
Surface Modeling ◽  
Quadratic Model ◽  
Response Surface Modeling ◽  
Prediction Errors ◽  
Order Kinetic ◽  
Order Kinetic Model ◽  
Process Factors

Chitosan/feldspar biobased beads were synthesized, characterized, and tested for the removal of Acid Black 1 dye from aquatic phases. A four-factor central composite design (CCD) accompanied by response surface modeling (RSM) and optimization was used to optimize the dye adsorption by the adsorbent (chitosan/feldspar composite) in 31 different batch experiments. Independent variables of temperature, pH, initial dye concentration, and adsorbent dose were used to change to coded values. To anticipate the responses, a quadratic model was applied. Analysis of variance (ANOVA) tested the significance of the process factors and their interactions. The adequacy of the model was investigated by the correlation between experimental and predicted data of the adsorption and the calculation of prediction errors. The results showed that the predicted maximum adsorption amount of 21.63 mg/g under the optimum conditions (pH 3, temperature 15°C, initial dye concentration 125 mg/L, and dose 0.2 g/50 mL) was close to the experimental value of 19.85 mg/g. In addition, the results of adsorption behaviors of the dye illustrated that the adsorption process followed the Langmuir isotherm model and the pseudo-second-order kinetic model. Langmuir sorption capacity was found to be 17.86 mg/g. Besides, thermodynamic parameters were evaluated and revealed that the adsorption process was exothermic and favourable.

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

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 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.

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