scholarly journals Removal of Hg2+ with Polypyrrole-Functionalized Fe3O4/Kaolin: Synthesis, Performance and Optimization with Response Surface Methodology

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1370
Author(s):  
Zhenfeng Lin ◽  
Ziwei Pan ◽  
Yuhao Zhao ◽  
Lin Qian ◽  
Jingtao Shen ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Adsorption Process ◽  
Low Cost ◽  
Solution Ph ◽  
Central Composite Designs ◽  
Pseudo Second Order ◽  
Composite Designs ◽  
Central Composite ◽  
Relevant Factors

PPy-Fe3O4/Kaolin was prepared with polypyrrole functionalized magnetic Kaolin by a simple, green, and low cost method to improve the agglomeration and low adsorption capacity of Kaolin. PPy-Fe3O4/Kaolin was employed to remove Hg2+ and the results were characterized by various methods. Relevant factors, including solution pH, dosage of adsorbent, concentration (C0), and temperature (T), were optimized by Response Surface Methodology (RSM) and Central Composite Designs (CCD). The optimal results show that the importance for adsorption factors is pH > T > C0 > dosage, and the optimal adsorption conditions of PPy-Fe3O4/Kaolin are pH = 7.2, T = 315 K, C0 = 50 mg/L, dosage of 0.05 g/L, and the capacity is 317.1 mg/g. The adsorption process conforms to the pseudo-second-order and Langmuir models. Dubinin–Radushkevich model shows that adsorption process is spontaneous and endothermic. Moreover, the adsorption of mercury by PPy-Fe3O4/Kaolin was achieved mainly through electrostatic attraction, pore diffusion, and chelation between amino functional groups and Hg2+. PPy-Fe3O4/Kaolin has excellent reproducibility, dispersity, and chemical stability, and it is easy to be separated from solution through an external magnetic field. The experiments show that PPy-Fe3O4/Kaolin is an efficient and economical adsorbent towards mercury.

scholarly journals Useful Numerical Statistics of Some Response Surface Methodology Designs

2016 ◽  
Vol 8 (4) ◽  
pp. 40
Author(s):  
Iwundu M. P.
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Optimality Criteria ◽  
Second Order ◽  
First Order ◽  
Central Composite Designs ◽  
Alphabetic Optimality ◽  
Main Effects ◽  
Composite Designs ◽  
Central Composite

<p>Useful numerical evaluations associated with three categories of Response Surface Methodology designs are presented with respect to five commonly encountered alphabetic optimality criteria. The first-order Plackett-Burman designs and the  Factorial designs are examined for the main effects models and the complete first-order models respectively. The second-order Central Composite Designs are examined for second-order models. The A-, D-, E-, G- and T-optimality criteria are employed as commonly encountered optimality criteria summarizing how good the experimental designs are. Relationships among the optimality criteria are pointed out with regards to the designs and the models. Generally the designs do not show uniform preferences in terms of the considered optimality criteria. However, one interesting finding is that central composite designs defined on cubes and hypercubes with unit axial distances are uniformly preferred in terms of E-optimality and G-optimality criteria.</p>

scholarly journals Alternative Second-Order N-Point Spherical Response Surface Methodology Design and Their Efficiencies

2016 ◽  
Vol 5 (4) ◽  
pp. 22
Author(s):  
Mary Paschal Iwundu
Keyword(s):  
Response Surface Methodology ◽  
Central Composite Design ◽  
Response Surface ◽  
Second Order ◽  
The Face ◽  
Central Composite Designs ◽  
Face Centered ◽  
Composite Designs ◽  
Central Composite ◽  
Exact Designs

The equiradial designs are studied as alternative second-order N-point spherical Response Surface Methodology designs in two variables, for design radius ρ = 1.0. These designs are seen comparable with the standard second-order response surface methodology designs, namely the Central Composite Designs. The D-efficiencies of the equiradial designs are evaluated with respect to the spherical Central Composite Designs. Furthermore, D-efficiencies of the equiradial designs are evaluated with respect to the D-optimal exact designs defined on the design regions of the Circumscribed Central Composite Design, the Inscribed Central Composite Design and the Face-centered Central Composite Design. The D-efficiency values reveal that the alternative second-order N-point spherical equiradial designs are better than the Inscribed Central Composite Design though inferior to the Circumscribed Central Composite Design with efficiency values less than 50% in all cases studied. Also, D-efficiency values reveal that the alternative second-order N-point spherical equiradial designs are better than the N-point D-optimal exact designs defined on the design region supported by the design points of the Inscribed Central Composite Design. However, the N-point spherical equiradial designs are inferior to the N-point D-optimal exact designs defined on the design region supported by the design points of the Circumscribed Central Composite Design and those of the Face-centered Central Composite Design, with worse cases with respect to the design region of the Circumscribed Central Composite Design.

scholarly journals Evaluation and Comparison of Three Classes of Central Composite Designs

2021 ◽  
pp. 31-47
Author(s):  
Fidelia Chinenye Kiwu-Lawrence ◽  
Lawrence Chizoba Kiwu ◽  
Desmond Chekwube Bartholomew ◽  
Chukwudi Paul Obite ◽  
Akanno Felix Chikereuba
Keyword(s):  
Response Surface Methodology ◽  
Central Composite Design ◽  
Response Surface ◽  
Central Composite Designs ◽  
Face Centered ◽  
Composite Designs ◽  
Composite Face ◽  
Central Composite

Three classes of Central Composite Design: Central Composite Circumscribed Design (CCCD), Central Composite Inscribed Design (CCID) and Central Composite Face-Centered Design (CCFD) in Response Surface Methodology (RSM) were evaluated and compared using the A-, D-, and G-efficiencies for factors, k, ranging from 3 to 10, with 0-5 centre points, in other to determine the performances of the designs under consideration. The results show that the CCDs (CCCD, CCFD and CCID) are at their best when the G-efficiency is employed for all the factors considered while the CCID especially behaves poorly when using the A- and D-efficiencies.

Optimization of Fermentation Medium for Pullulan Production by Aureobasidium pullulans A225 Using Plackett-Burman and Response Surface Methodology

2013 ◽  
Vol 785-786 ◽  
pp. 279-286
Author(s):  
Yu Feng Xie ◽  
Xiao Lei Ma ◽  
Yun Feng Gao ◽  
Xing Da Lu
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Fermentation Medium ◽  
Medium Composition ◽  
Steepest Ascent ◽  
Optimal Region ◽  
Central Composite Designs ◽  
Optimization Of Fermentation ◽  
Composite Designs ◽  
Central Composite

In this study, response surface methodology (RSM) was used to optimize the medium based on the PlackettBurman and Central-Composite Designs for the production of pullulan using a strain of Auerobasidium pullulans A225. Peptone, K2HPO4, and MgSO4 were found to have significant effects on pullulan production using the PlackettBurman Design. The steepest ascent experiment was adopted to determine the optimal region of the medium composition. The concentrations of the three above mentioned compounds were further optimized using the Central-Composite Design. Results showed that the final concentration of medium optimized using RSM was 6.34 g/L peptone, 7.91 g /L K2HPO4, and 0.46 g/L MgSO4. Production of pullulan reached 72.56 g/L under the optimized medium.

Response Surface Methodology Central-Composite Design Modifications for Human Performance Research

1973 ◽  
Vol 15 (4) ◽  
pp. 295-310 ◽  
Author(s):  
Christine Clark ◽  
Robert C. Williges
Keyword(s):  
Response Surface Methodology ◽  
Central Composite Design ◽  
Response Surface ◽  
Human Performance ◽  
Experimental Point ◽  
Multiple Observations ◽  
Central Composite Designs ◽  
Composite Designs ◽  
Performance Research ◽  
Central Composite

Selected response surface methodology (RSM) designs that are viable alternatives in human performance research are discussed. Two major RSM designs that are variations of the basic, blocked, central-composite design have been selected for consideration: (1) central-composite designs with multiple observations at only the center point, and (2) central-composite designs with multiple observations at each experimental point. Designs of the latter type are further categorized as: (a) designs which collapse data across all observations at the same experimental point; (b) between-subjects designs in which no subject is observed more than once, and observations at each experimental point may be multiple and unequal or multiple and equal; and (c) within-subject designs in which each subject is observed only once at each experimental point. The ramifications of these designs are discussed in terms of various criteria such as rotatability, orthogonal blocking, and estimates of error.

scholarly journals Optimization of Methylene Blue Adsorption on Agricultural Solid Waste Using Box–Behnken Design (BBD) Combined with Response Surface Methodology (RSM) Modeling

2021 ◽  
Vol 12 (4) ◽  
pp. 4567-4583
Keyword(s):  
Methylene Blue ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Contact Time ◽  
Organic Dyes ◽  
Low Cost ◽  
Sem Analysis ◽  
Solution Ph ◽  
Box Behnken Design ◽  
Mb Adsorption

Tunics corm saffron (TCS) is a low-cost adsorbent that removes methylene blue (MB) from an aqueous solution. The TCS was characterized using FTIR and SEM analysis. The influence of MB adsorption variables such as TCS dose (0.4–2.4 g L−1), contact time (0–120 min), MB dye concentration (100–500 mg L−1) was optimized Box–Behnken design (BBD) combined with response surface methodology (RSM) modeling. All three variables among the main parameters significantly affected the removal efficiency by applying the quadratic regression analysis. The results showed that the predicted values for MB adsorption were close to the experimental values and were in good agreement. Besides, the r2 value (r2=0.970) indicates that the regression can predict response for the adsorption process in the studied range. The optimum BBD-RSM for MB removal of 89.48 % was recorded at a TCS dose of 1.78 g L−1, contact time of 56 min, MB dye concentration of 176 mg L–1 at solution pH of 5.4 temperature 21 °C. Excellent regeneration of TCS to remove MB in sixth consecutive adsorption-desorption cycles. This work highlights that TCS offers tremendous potential as a low-cost for organic dyes removal from wastewaters.

scholarly journals Treatment of effluent from fertilizer industry by adsorption on willow sawdust-removal of Ni(II) and Cd(II) from the effluent

2021 ◽  
pp. 1-12
Author(s):  
Raafia Najam ◽  
Syed Muzaffar Ali Andrabi
Keyword(s):  
Aqueous Solution ◽  
Adsorption Process ◽  
Low Cost ◽  
Second Order ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
The World ◽  
Pseudo Second Order ◽  
Almost All ◽  
Willow Tree

Sawdust of willow has been investigated as an adsorbent for the removal of Ni(II), and Cd(II) ions from aqueous solution. Since willow tree is widely grown in almost all parts of Kashmir, it can be a common most easily available, sustainable, low cost adsorbent for the treatment of wastewaters in this part of the world where growing industrialization is affecting water quality like elsewhere in the world. Therefore, it is worthwhile to investigate the potential of sawdust of willow tree as an adsorbent for the removal of Ni(II) and Cd(II) ions from aqueous solution as a first step. Batch experiments were conducted to study the effect of some parameters such as contact time, initial concentration of metal ions, solution pH and temperature. Langmuir and Freundlich models were employed for the mechanistic analysis of experimental data obtained. Results reveal that in our system adsorption follows the Langmuir isotherm. The maximum adsorption capacity of Ni(II) and Cd(II) were found to be 7.98 and 7.11 mg/g respectively at optimum conditions. The pseudo-first-order and pseudo-second-order models were employed for kinetic analysis of adsorption process. The adsorption process follows pseudo-second-order kinetics. The efficacy of the adsorbent in the treatment of effluent from fertilizer factory has been investigated and the results have been found encouraging.

Application of Response Surface Methodology for Optimization of Methylene Blue Removal by Casuarina equitifolia Leaves Powder

2015 ◽  
Vol 1113 ◽  
pp. 745-750
Author(s):  
Norzila Mohd ◽  
Wan Hasnidah Wan Osman ◽  
Mohd Shahrul Nizam Salleh ◽  
Sarifah Fauziah Syed Draman ◽  
Nurul Syahirah Abd Kahar ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Adsorption Process ◽  
Coefficient Of Determination ◽  
Human Beings ◽  
Adsorbent Dosage ◽  
Mutagenic Effects ◽  
Central Composite

Dye is a type of colorants that are widely used in many industries. Many dyes are toxic in nature with suspected carcinogenic and mutagenic effects that affect aquatic lives and also human beings. Adsorption process is considered as eco-friendly method to remove color from the aqueous solution compared to other established method. In this study, Casuarina Equitifolia leaves were used as an adsorbent. The Response surface methodology (RSM) was employed, using a central composite design (CCD) to optimize the three important variables, i.e., initial dye concentration, pH of the dye solution and adsorbent dosage in order to remove of methylene blue from aqueous solution. From the analysis of variance (ANOVA), the value (>0.8) of the coefficient of determination (R2) was obtained. The optimal condition was established at pH 6.91, 0.1 g adsorbent dosage and 10ppm initial methylene blue concentration. The removal efficiency was found to be 98.80%. From the findings, it shows that Casuarina Equitifolia leaves powder is suitable to be used as an adsorbent in removal of color from aqueous solution.

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