Optimization of operating parameters for efficient photocatalytic inactivation of Escherichia coli based on a statistical design of experiments

2015 ◽  
Vol 71 (6) ◽  
pp. 823-831 ◽  
Author(s):  
Mehrzad Feilizadeh ◽  
Iran Alemzadeh ◽  
Amin Delparish ◽  
M. R. Karimi Estahbanati ◽  
Mahdi Soleimani ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Reaction Temperature ◽  
High Performance ◽  
Statistical Design ◽  
Water Disinfection ◽  
Response Analysis ◽  
Operating Parameters ◽  
Statistical Design Of Experiments ◽  
Photocatalytic Disinfection ◽  
Initial Ph

In this work, the individual and interaction effects of three key operating parameters of the photocatalytic disinfection process were evaluated and optimized using response surface methodology (RSM) for the first time. The chosen operating parameters were: reaction temperature, initial pH of the reaction mixture and TiO2 P-25 photocatalyst loading. Escherichia coli concentration, after 90 minutes irradiation of UV-A light, was selected as the response. Twenty sets of photocatalytic disinfection experiments were conducted by adjusting operating parameters at five levels using the central composite design. Based on the experimental data, a semi-empirical expression was established and applied to predict the response. Analysis of variance revealed a strong correlation between predicted and experimental values of the response. The optimum values of the reaction temperature, initial pH of the reaction mixture and photocatalyst loading were found to be 40.3 °C, 5.9 g/L, and 1.0 g/L, respectively. Under the optimized conditions, E. coli concentration was observed to reduce from 107 to about 11 CFU/mL during the photocatalytic process. Moreover, all these results showed the great significance of the RSM in developing high performance processes for photocatalytic water disinfection.

scholarly journals Synthesis of an Addition-Crosslinkable, Silicon-Modified Polyolefin via Reactive Extrusion Monitored by In-Line Raman Spectroscopy

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1246
Author(s):  
Steffen Ulitzsch ◽  
Tim Bäuerle ◽  
Mona Stefanakis ◽  
Marc Brecht ◽  
Thomas Chassé ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
High Performance ◽  
Process Analytical Technology ◽  
Statistical Design ◽  
Reactive Extrusion ◽  
Statistical Design Of Experiments ◽  
Grafting Efficiency ◽  
Grafting Reaction ◽  
Central Composite Experimental Design ◽  
Process Factors

We present the modification of ethylene-propylene rubber (EPM) with vinyltetra-methydisiloxane (VTMDS) via reactive extrusion to create a new silicone-based material with the potential for high-performance applications in the automotive, industrial and biomedical sectors. The radical-initiated modification is achieved with a peroxide catalyst starting the grafting reaction. The preparation process of the VTMDS-grafted EPM was systematically investigated using process analytical technology (in-line Raman spectroscopy) and the statistical design of experiments (DoE). By applying an orthogonal factorial array based on a face-centered central composite experimental design, the identification, quantification and mathematical modeling of the effects of the process factors on the grafting result were undertaken. Based on response surface models, process windows were defined that yield high grafting degrees and good grafting efficiency in terms of grafting agent utilization. To control the grafting process in terms of grafting degree and grafting efficiency, the chemical changes taking place during the modification procedure in the extruder were observed in real-time using a spectroscopic in-line Raman probe which was directly inserted into the extruder. Successful grafting of the EPM was validated in the final product by 1H-NMR and FTIR spectroscopy.

Kinetic of C.I. Reactive Black 5 by Fenton-Like Oxidation

2013 ◽  
Vol 690-693 ◽  
pp. 1512-1515
Author(s):  
Yi Jun Du ◽  
Guo Peng Jiang ◽  
Xin Ping Fang ◽  
Mu Qing Qiu
Keyword(s):  
Reaction Temperature ◽  
Oxidation Process ◽  
Solution Concentration ◽  
Operating Parameters ◽  
Reactive Black 5 ◽  
H2o2 Concentration ◽  
System Parameters ◽  
First Order ◽  
First Order Kinetics ◽  
Initial Ph

The decolorization kinetic of C.I. Reactive Black 5 was studied using Fenton-like oxidation. The effect of the major system parameters, such as initial pH of the solution, concentration of H2O2, concentration of Fe3+ and reaction temperature on the kinetics was determined. The results indicate that the operating parameters, such as initial pH of dye solution, initial concentration of Fe2+ and H2O2, reaction temperature, have strong influences on the degradation of C.I. Reactive Black 5 by Fenton-like oxidation process. In addition, it was also found that the decolorization of C.I. Reactive Black 5 followed the first-order kinetics well.

scholarly journals Photocatalytic Treatment of An Actual Confectionery Wastewater Using Ag/TiO2/Fe2O3: Optimization of Photocatalytic Reactions Using Surface Response Methodology

Catalysts ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 409 ◽  
Author(s):  
Yi Lin ◽  
Mehrab Mehrvar
Keyword(s):  
Statistical Design ◽  
Optimization Method ◽  
Order Rate Constant ◽  
Light Wavelength ◽  
Statistical Design Of Experiments ◽  
Toc Removal ◽  
Initial Ph ◽  
Photocatalytic Reactions ◽  
The Individual ◽  
Independent Parameters

Titanium dioxide (TiO2) photocatalysis is one of the most commonly studied advanced oxidation processes (AOPs) for the mineralization of deleterious and recalcitrant compounds present in wastewater as it is stable, inexpensive, and effective. Out of all, doping with metal and non-metals, and the heterojunction with another semiconductor were proven to be efficient methods in enhancing the degradation of organic pollutants under ultraviolet (UV) and visible light. However, complex degradation processes in the treatment of an actual wastewater are difficult to model and optimize. In the present study, the application of a modified photocatalyst, Ag/TiO2/Fe2O3, for the degradation of an actual confectionery wastewater was investigated. Factorial studies and statistical design of experiments using the Box-Behnken method along with response surface methodology (RSM) were employed to identify the individual and cross-factor effects of independent parameters, including light wavelength (nm), photocatalyst concentration (g/L), initial pH, and initial total organic carbon (TOC) concentration (g/L). The maximum TOC removal at optimum conditions of light wavelength (254 nm), pH (4.68), photocatalyst dosage (480 mg/L), and initial TOC concentration (11,126.5 mg/L) was determined through the numerical optimization method (9.78%) and validated with experimental data (9.42%). Finally, the first-order rate constant with respect to TOC was found to be 0.0005 min−1 with a residual value of 0.998.

scholarly journals Optimization of the Microwave Assisted Glycosylamines Synthesis Based on a Statistical Design of Experiments Approach

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5121
Author(s):  
Jo Sing Julia Tang ◽  
Kristin Schade ◽  
Lucas Tepper ◽  
Sany Chea ◽  
Gregor Ziegler ◽  
...  
Keyword(s):  
Design Of Experiments ◽  
Reaction Temperature ◽  
Glucuronic Acid ◽  
Statistical Design ◽  
Strong Indication ◽  
Statistical Design Of Experiments ◽  
Microwave Assisted ◽  
Amination Reaction ◽  
Range Of Functions ◽  
Vast Range

Glycans carry a vast range of functions in nature. Utilizing their properties and functions in form of polymers, coatings or glycan derivatives for various applications makes the synthesis of modified glycans crucial. Since amines are easy to modify for subsequent reactions, we investigated regioselective amination conditions of different saccharides. Amination reactions were performed according to Kochetkov and Likhoshertov and accelerated by microwave irradiation. We optimized the synthesis of glycosylamines for N-acetyl-d-galactosamine, d-lactose, d-glucuronic acid and l-(−)-fucose using the design of experiments (DoE) approach. DoE enables efficient optimization with limited number of experimental data. A DoE software generated a set of experiments where reaction temperature, concentration of carbohydrate, nature of aminating agent and solvent were investigated. We found that the synthesis of glycosylamines significantly depends on the nature of the carbohydrate and on the reaction temperature. There is strong indication that high temperatures are favored for the amination reaction.

scholarly journals Photocatalytic Treatment of An Actual Confectionery Wastewater Using Ag/TiO2/Fe2O3: Optimization of Photocatalytic Reactions Using Surface Response Methodology.

2021 ◽  
Author(s):  
Yi-Ping Lin ◽  
Mehrab Mehrvar
Keyword(s):  
Statistical Design ◽  
Optimization Method ◽  
Order Rate Constant ◽  
Light Wavelength ◽  
Statistical Design Of Experiments ◽  
Toc Removal ◽  
Initial Ph ◽  
Photocatalytic Reactions ◽  
The Individual ◽  
Independent Parameters

Titanium dioxide (TiO2) photocatalysis is one of the most commonly studied advanced oxidation processes (AOPs) for the mineralization of deleterious and recalcitrant compounds present in wastewater as it is stable, inexpensive, and effective. Out of all, doping with metal and non-metals, and the heterojunction with another semiconductor were proven to be efficient methods in enhancing the degradation of organic pollutants under ultraviolet (UV) and visible light. However, complex degradation processes in the treatment of an actual wastewater are difficult to model and optimize. In the present study, the application of a modified photocatalyst, Ag/TiO2/Fe2O3, for the degradation of an actual confectionery wastewater was investigated. Factorial studies and statistical design of experiments using the Box-Behnken method along with response surface methodology (RSM) were employed to identify the individual and cross-factor effects of independent parameters, including light wavelength (nm), photocatalyst concentration (g/L), initial pH, and initial total organic carbon (TOC) concentration (g/L). The maximum TOC removal at optimum conditions of light wavelength (254 nm), pH (4.68), photocatalyst dosage (480 mg/L), and initial TOC concentration (11,126.5 mg/L) was determined through the numerical optimization method (9.78%) and validated with experimental data (9.42%). Finally, the first-order rate constant with respect to TOC was found to be 0.0005 min−1 with a residual value of 0.998.

scholarly journals Photocatalytic Treatment of An Actual Confectionery Wastewater Using Ag/TiO2/Fe2O3: Optimization of Photocatalytic Reactions Using Surface Response Methodology.

2021 ◽  
Author(s):  
Yi-Ping Lin ◽  
Mehrab Mehrvar
Keyword(s):  
Statistical Design ◽  
Optimization Method ◽  
Order Rate Constant ◽  
Light Wavelength ◽  
Statistical Design Of Experiments ◽  
Toc Removal ◽  
Initial Ph ◽  
Photocatalytic Reactions ◽  
The Individual ◽  
Independent Parameters

Titanium dioxide (TiO2) photocatalysis is one of the most commonly studied advanced oxidation processes (AOPs) for the mineralization of deleterious and recalcitrant compounds present in wastewater as it is stable, inexpensive, and effective. Out of all, doping with metal and non-metals, and the heterojunction with another semiconductor were proven to be efficient methods in enhancing the degradation of organic pollutants under ultraviolet (UV) and visible light. However, complex degradation processes in the treatment of an actual wastewater are difficult to model and optimize. In the present study, the application of a modified photocatalyst, Ag/TiO2/Fe2O3, for the degradation of an actual confectionery wastewater was investigated. Factorial studies and statistical design of experiments using the Box-Behnken method along with response surface methodology (RSM) were employed to identify the individual and cross-factor effects of independent parameters, including light wavelength (nm), photocatalyst concentration (g/L), initial pH, and initial total organic carbon (TOC) concentration (g/L). The maximum TOC removal at optimum conditions of light wavelength (254 nm), pH (4.68), photocatalyst dosage (480 mg/L), and initial TOC concentration (11,126.5 mg/L) was determined through the numerical optimization method (9.78%) and validated with experimental data (9.42%). Finally, the first-order rate constant with respect to TOC was found to be 0.0005 min−1 with a residual value of 0.998.

scholarly journals Optimization of Arabian-Shield-Based Natural Pozzolan and Silica Fume for High-Performance Concrete Using Statistical Design of Experiments

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Yassir M. Abbas ◽  
M. Iqbal Khan
Keyword(s):  
Silica Fume ◽  
High Performance ◽  
Prediction Models ◽  
High Performance Concrete ◽  
Blended Cement ◽  
Statistical Design ◽  
Partial Replacement ◽  
Statistical Design Of Experiments ◽  
Natural Pozzolan ◽  
Surface Design

In this study, the optimum dosages of silica fume (SF) and natural pozzolan (NP) were experimentally and statistically assessed for the best strength and durability properties of high-performance concrete (HPC). SF and NP were used as partial replacement Portland cement (PC) by up to 12 and 25 wt.%, respectively. Additionally, the prediction models based on second-level factorial (SLF) and response surface design (RSD) were formulated to estimate the HPC properties and their validation. The SLF-based model was further employed to investigate the significance and interactions of the PC, SF, and NP blends. The 28-day strength of the blended-cement HPC with a water-to-binder ratio w / b of 0.25 was generally higher than that of the control concrete. The positive synergy of PC–NP–SF was also observed in the HPC permeability. The paired t -test of the mean square error (MSE) of the SLF- and RSD-based models revealed that the MSE of the former was notably less than that of the latter. These results established the superiority of the SLF-based model over the RSD-based model. Therefore, the SLF-based model was further employed to investigate the importance of various binders.

A CFD-Based Robust Design of Operating Conditions for an HVAC System

2013 ◽  
Author(s):  
Luis F. Arias ◽  
Antonio J. Bula Silvera ◽  
Marco E. Sanjuan
Keyword(s):  
Robust Design ◽  
Air Conditioning ◽  
Geographical Area ◽  
Statistical Design ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Basic Operation ◽  
Hvac System ◽  
Statistical Design Of Experiments ◽  
Air Velocity

HVAC systems are directly related to comfort (human health, productivity, etc.) and energy consumption. Depending on the application and geographical area, they may become a key disruptive and energy starving system. The research discussed in this paper describes a CFD-based approach for robust HVAC system design aimed at reducing variability in the conditioned area by adjusting operating parameters. Since robust design techniques aim at minimum variance (via S/N ratio), the solutions obtained allow the selection of operating parameters leading to more uniform distribution. Three variables were used: air velocity (to control energy transfer from people to the surrounding air), Unit usage (a ratio to consider the air conditioning system inertia compared to air conditioning requirements), and room temperature set point (representing the relation between the machine and the conditions room). Embedded codes with field functions in the CFD software allow the simulation of a very basic operation strategy, and demonstrate a quasi-dynamic operation for different cooling capacities and air velocity. Results allow allocating operating parameters that lead to a more uniform temperature and relative humidity distributions, therefore, this approach can be adequately combined with statistical design of experiments for better conditions.

STATISTICAL DESIGN OF EXPERIMENTS FOR THE Cr(VI) ADSORPTION ON WEED Salvinia cucullata

2013 ◽  
Vol 12 (3) ◽  
pp. 465-474 ◽  
Author(s):  
Saroj Sundar Baral ◽  
Ganesan Surendran ◽  
Namrata Das ◽  
Polisetty Venkateswara Rao
Keyword(s):  
Design Of Experiments ◽  
Statistical Design ◽  
Statistical Design Of Experiments
Sign in / Sign up

Export Citation Format

Share Document