Comparative Analysis of the Adsorption of Methylene Blue Using Magnetised and Non-Magnetised Coconut Shell Biochar

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
A Musa
Keyword(s):  
Methylene Blue ◽  
Nonlinear Regression ◽  
Error Function ◽  
Coconut Shell ◽  
Isotherm Models ◽  
P Value ◽  
Regression Methods ◽  
Best Fit ◽  
Coconut Shell Biochar ◽  
Mb Adsorption

It is envisaged that magnetisation might alter the sorption behaviours of magnetised biochars due to some variation in the physicochemical properties from their precursor. This study evaluated the adsorption behaviours of a coconut shell biochar produced at 600 °C, CSB600, and its magnetised pair, MCSB600, in the adsorption of methylene blue (MB) from aqueous solutions. Langmuir, Freundlich and Redlich-Peterson isotherm models were used to describe the experimental isotherm using linear and nonlinear regression methods to determine the best fit for MB adsorption from the batch experiments conducted. The Langmuir model proved to be the best fit to explain the experimental data as it had the highest R2 (0.9684 and 0.9855) from linear regression and the lowest hybrid fractional error function, HYBRID (4.58, 1.145) and marquardt’s percent standard deviation, MPSD (10.61, 5.04) error function values from the nonlinear regression methods with maximum monolayer adsorption capacities of 5.590 and 5.229 mg/g for CSB600 and MCSB600 respectively. The magnetised biochar exhibited similar adsorption characteristics to what was observed for the non-magnetised biochar and only about 6.46% lower MB adsorption capacity was recorded. A p-value of 0.088 obtained suggested the isotherms were similar and therefore, magnetisation did not affect the adsorption of MB.

AI Techniques to Estimate Muscle Force and Joint Torque for Upper Extremity

2011 ◽  
Vol 467-469 ◽  
pp. 788-793 ◽  
Author(s):  
S. Parasuraman ◽  
Arif Wicaksono Oyong ◽  
Veronica Lestari Jauw
Keyword(s):  
Experimental Data ◽  
Nonlinear Regression ◽  
Stroke Rehabilitation ◽  
Muscle Force ◽  
Joint Torque ◽  
Robot Assisted ◽  
Unknown Parameters ◽  
Regression Methods ◽  
Voluntary Contractions ◽  
Best Fit

This paper is motivated by works done in the area of robot-assisted stroke rehabilitation. To map the EMG to joint torque, evolutionary techniques with suitable mathematical models are proposed. These models have unknown adjustable parameters, and the values of these parameters are obtained using nonlinear regression methods such as GA and SA. Five subjects took part in the experiments and they were asked to perform non-fatiguing and variable force maximal voluntary contractions and sub-maximal voluntary contractions. The recorded EMG signals data of various joints are entered to the model, to estimate the best fit values for the unknown parameters. Once these values of the parameters are obtained they are applied into the model and thus the joint torque is estimated. Predictions made by the proposed techniques are well correlated with experimental data.

scholarly journals Synthesis of PANI@ZnO Hybrid Material and Evaluations in Adsorption of Congo Red and Methylene Blue Dyes: Structural Characterization and Adsorption Performance

2021 ◽  
Author(s):  
Imane Toumi ◽  
Halima Djelad ◽  
Faiza Chouli ◽  
Benyoucef Abdelghani
Keyword(s):  
Methylene Blue ◽  
Congo Red ◽  
Average Pore Size ◽  
Isotherm Models ◽  
Order Model ◽  
Average Pore ◽  
Freundlich Model ◽  
Pseudo Second Order ◽  
Adsorption Desorption ◽  
Best Fit

Abstract In this research, a simple oxidation chemical process was applied for the synthesis of novel PANI@ZnO nanocomposite. The prepared nanocomposites were characterized by XPS, XRD, FTIR, SEM, TGA and N2 adsorption-desorption isotherms. Thereby, PANI@ZnO highest SBET values (about 40.84 m2.g− 1), total mesoporous volume (about 3.214 cm3.g− 1) and average pore size (about 46.12 nm). Afterwards, the prepared nanomaterial was applied as novel nanoadsorbent for the adsorption of Congo Red (CR) and Methylene Blue (MB) dyes from aqueous solutions at 298 K and pH 5.0. Besides, the pseudo-second-order model was obtained the best for the adsorption of both dyes. In the case of isotherm models, the Freundlich model showed the best fit. After removal, the spent adsorbent was regenerated. With the regeneration repeated five cycles, the PANI@ZnO regeneration efficiency remained at a very adequate level.

scholarly journals Isotherm Studies of Adsorption of Methylene Blue by Palm Kernel Shell

2018 ◽  
pp. 1-9
Author(s):  
Oladokun Benjamen Niran ◽  
Salaudeen Abdulwasiu Olawale ◽  
Utam John Ushie
Keyword(s):  
Methylene Blue ◽  
Adsorption Process ◽  
Palm Kernel ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Suitable Model ◽  
Palm Kernel Shell ◽  
Freundlich Adsorption Isotherm ◽  
Langmuir And Freundlich Models ◽  
Mb Adsorption

The main aim of this work is determine the feasibility of palm kernel shell (PKS) with phosphoric acid impregnation to biosorb methylene blue (MB) from aqueous solution by carrying out isotherm studies of the process. The influence of various factors such as contact time, initial dye concentration, adsorbent dosage, pH of dye solution and temperature were investigated in a batch adsorption technique. Result showed that adsorption of methylene blue (MB) dye was favourable at acidic pH. The percentage adsorption was found to increase with time of agitation, temperature, and mass of adsorbent but decreased with increase in initial MB concentration. In order to obtain a suitable model for the MB adsorption process, obtained data were fitted into different isotherm models like Langmuir and Freundlich models. Results showed that Freundlich adsorption isotherm model best describe MB adsorption onto palm kernel shell (PKS).

scholarly journals Adsorption of methylene blue on corncob charcoal: Thermodynamic studies

2021 ◽  
Vol 23 (1) ◽  
pp. 131-144
Author(s):  
A.A. Fodeke ◽  
O.J. Ayejuyone
Keyword(s):  
Methylene Blue ◽  
Thermodynamic Properties ◽  
Isotherm Model ◽  
Point Of Zero Charge ◽  
Isotherm Models ◽  
Thermodynamic Quantities ◽  
Zero Charge ◽  
Temperature Isotherm ◽  
Single Temperature ◽  
Mb Adsorption

To obtain the thermodynamic properties of adsorption of methylene blue (MB) on corncob carbonaceous adsorbents - untreated (UCC) and acid treated (TCC) - their equilibrium adsorption was determined between 10 o– 40o C at different pH conditions. The adsorption isotherms were fitted to Freundlich, Langmuir and Temkin isotherm models. The point of zero charge of each of the adsorbents was also determined. The point of zero charge was 10.58 ±0.09 for TCC, and 7.55 ± 0.10 for UCC. Only Freundlich model could account for the observed thermodynamic properties of MB adsorption by the adsorbents, though Temkin and Langmuir models have higher correlation coefficients. MB adsorption by TCC was an entropically driven process which depends on pH;ΔSo at pH 10.5 < ΔSo at pH 8.0 <ΔSo at pH 12.0. The ΔHo of the endothermic process at pH 12 is > ΔHo at pH 8 > ΔHo at pH 10.5. The results suggest that MB adsorption by the adsorbents occur by physisorption and is optimum when the pH is around the point of zero charge. It is important to ensure that in addition to fitting and equilibrium adsoption data by an isotherm model, the fit of the relevant equilibrium parameter should also be good and give thermodynamic quantities that could satisfactorily account for the observed adsorption properties of the system.  Deciding the suitability of an isotherm model for fitting adsorption equilibrium experiment based on compared error function of the fitted curves or lines through single temperature isotherm could lead to erroneous conclusion. Keywords: adsorption, adsorbent; methylene blue; enthalpy; entropy; Freundlich

scholarly journals Coconut shell-based activated carbon as adsorbent for the removal of dye from aqueous solution: equilibrium, kinetics, and thermodynamic studies

2021 ◽  
Vol 39 (4) ◽  
pp. 1076-1084
Author(s):  
O. Oribayo ◽  
O.O. Olaleye ◽  
A.S. Akinyanju ◽  
K.O. Omoloja ◽  
S.O. Williams
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Activated Carbon ◽  
Kinetic Data ◽  
Ph Value ◽  
Waste Water Treatment ◽  
Second Order ◽  
Coconut Shell ◽  
Isotherm Models ◽  
Pseudo Second Order

The need to develop more efficient adsorbent, comparable to commercially available adsorbent, is attracting significant interest as promising adsorbent for waste water treatment. In this study, the potential of activated carbon prepared from waste coconut shell (CSAC) for the removal of methylene blue (Mb) from aqueous solution was reported. Batch experiments were conducted to determine the adsorption isotherm and kinetics of Mb on CSAC. Langmuir, Freundlich and Temkin isotherm models were employed to fit and analyze the adsorption equilibrium data. The result shows Langmuir isotherm model gave the best fit and an adsorption capacity of 320.5 mg/g was obtained for Mb at pH value of 7, 0.02 g adsorbent dosage and contact time of 4.5 hour. The experimental kinetic data at different initial Mb concentrations was also analyzed with pseudo-first order, pseudo-second order and intraparticle diffusion models. The obtained results showed that the pseudo-second order model fits the adsorption kinetic data with R2 range of0.9985-0.9996. Finally, the thermodynamic parameters show that the adsorption of Mb on CSAC was spontaneous and endothermic in nature. This therefore suggests that (CSAC) is a viable adsorbent for effective removal of dye from wastewater effluent. Keywords: Activated carbon, Adsorption isotherms, Coconut shells, Methylene blue, kinetics.

scholarly journals Enhanced adsorption of methylene blue from textile wastewater by using natural and artificial zeolite

2020 ◽  
Author(s):  
Sinan Mehmet Turp ◽  
Güldane Aslı Turp ◽  
Necla Ekinci ◽  
Saim Özdemir
Keyword(s):  
Methylene Blue ◽  
Correlation Coefficient ◽  
Contact Time ◽  
Textile Wastewater ◽  
Isotherm Models ◽  
Isotherm Study ◽  
Adsorption Removal ◽  
Langmuir Isotherm Model ◽  
Enhanced Adsorption ◽  
Best Fit

Abstract This study investigated the adsorption of methylene blue with natural and artificial zeolite. The effect of pH, contact time, initial concentration and adsorbent dose on adsorption was also investigated. An artificial dye was prepared. Adsorption removal efficiency was low at pH = 2, 3 and 4 but it was quite high at pH = 7. It was determined that the contact time reaches equilibrium within 60 minutes in the adsorption of methylene blue with natural and artificial zeolite. The initial dyestuff concentration for both adsorbents was 5 mg/L. For the removal of methylene blue, a 0.5 g natural and artificial zeolite dosage was sufficient. In order to express the adsorption of natural and artificial zeolite on methylene blue, Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) isotherm models were examined. In the isotherm study, both natural and artificial zeolite adapted to the Langmuir isotherm model. Langmuir correlation coefficient was 0.998 for artificial zeolite and 0.993 for natural zeolite. Both adsorbent materials best fit into the pseudo-second kinetic model with similar correlation coefficient values of 0.999.

scholarly journals Determination of best-fit isotherm model for the sorption of Lead (II) and Manganese (II) ions onto acid-activated shale using selected non-linear error functions

2021 ◽  
Vol 5 (1) ◽  
pp. 11-19
Author(s):  
I. R. Ilaboya ◽  
J. S. Okpoko
Keyword(s):  
Standard Deviation ◽  
Error Function ◽  
Surface Characteristics ◽  
Isotherm Model ◽  
Isotherm Models ◽  
Error Functions ◽  
Function Computation ◽  
Normalized Error ◽  
Non Linear ◽  
Best Fit

The focus of this research is to apply the selected error function equation to establish the equilibrium isotherm model that best describes the adsorption of Pb2+ and Mn2+ onto acid-activated shale.  Data collected from the batch experiment were analyzed using selected isotherm models (Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Sips and Redlich-Peterson). To compute the isotherm parameters used in choosing the best-fit isotherm model, selected non-linear error functions, namely, error sum of the square, normalized standard deviation, hybrid error function, root mean square error and Marquardt’s percent standard deviation were employed. From the scanning electron microscope results, it was observed that the surface characteristics of the shale change considerably with calcination and acid treatment but the acid-treated shale shows better uneven porous surface characteristics. Error function computation shows that the Dubinin-Radushkevich isotherm model had the least sum of normalized error of 0.3623 for Pb2+ adsorption and 0.5465 for Mn2+ adsorption; hence, it was selected as the best isotherm model for explaining the sorption of Pb(II) and Mn(II) ions unto acid-activated shale.

Feedback Reactor and Nonlinear Regression Methods

1992 ◽  
Vol 57 (10) ◽  
pp. 2053-2058
Author(s):  
Václav Dušek ◽  
František Skopal
Keyword(s):  
Nonlinear Regression ◽  
Kinetic Measurements ◽  
Regression Methods ◽  
Linear And Nonlinear

Linear and nonlinear regression methods are compared with respect to their application to the evaluation of chemico-kinetic measurements of a feedback reactor. Their assets and pitfalls are demonstrated.

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