Optimization of photocatalytic degradation of naproxen from aqueous solutions with UV/ZnO process: Response Surface Methodology (RSM)

Response Surface ◽

Removal Efficiency ◽

Contact Time ◽

Operating Conditions ◽

Quadratic Model ◽

Order Model ◽

First Order ◽

Concentration Time ◽

The aim of this study was to optimize the removal of Naproxen (NPX) by the UV/ZnO photocatalytic process using response surface methodology based on Central Composite Design (CCD). The effect of parameters such as ZnO concentration, contact time, pH, temperature, and initial NPX concentration were studied. The ANOVA results indicated high coefficient values of adjusted R2 (0.9843) and predicted R2 (0.9695). The quadratic model with the highest R-squared designation was chosen to predict the NPX removal efficiency of the UV/ZnO process. Under optimal conditions that include an optimum initial NPX concentration of 21.59 mg/L, ZnO concentration of 371.15 mg/L, contact time of 73.92 min, pH of 6.87, and temperature of 24.35°C, a NPX removal efficiency value of 71.19% was obtained. The results show that the removal of NPX is most affected by the variables- initial NPX concentration, time, pH, and ZnO concentration, respectively, but temperature as a variable does not have a significant effect on the efficiency of the process. Moreover, the NPX photodegradation kinetics can be explained through the pseudo-first-order model. The UV/ZnO photocatalytic method has high potential for the removal of NPX, and that CCD is an appropriate method to optimize the operating conditions for NPX photodegradation.

Response surface methodology approach for the optimisation of adsorption of hydrolysed polyacrylamide from polymer-flooding wastewater onto steel slag: a good option of waste mitigation

Water Science & Technology ◽

10.2166/wst.2017.245 ◽

2017 ◽

Vol 76 (4) ◽

pp. 776-784 ◽

Cited By ~ 2

Author(s):

Mijia Zhu ◽

Jun Yao ◽

Zhonghai Qin ◽

Luning Lian ◽

Chi Zhang

Keyword(s):

Response Surface ◽

Removal Efficiency ◽

Contact Time ◽

Interactive Effect ◽

Steel Slag ◽

Oxygen Demand ◽

Polymer Flooding ◽

High Concentration ◽

Adsorbent Dosage

Wastewater produced from polymer flooding in oil production features high viscosity and chemical oxygen demand because of the residue of high-concentration polymer hydrolysed polyacrylamide (HPAM). In this study, steel slag, a waste from steel manufacturing, was studied as a low-cost adsorbent for HPAM in wastewater. Optimisation of HPAM adsorption by steel slag was performed with a central composite design under response surface methodology (RSM). Results showed that the maximum removal efficiency of 89.31% was obtained at an adsorbent dosage of 105.2 g/L, contact time of 95.4 min and pH of 5.6. These data were strongly correlated with the experimental values of the RSM model. Single and interactive effect analysis showed that HPAM removal efficiency increased with increasing adsorbent dosage and contact time. Efficiency increased when pH was increased from 2.6 to 5.6 and subsequently decreased from 5.6 to 9.3. It was observed that removal efficiency significantly increased (from 0% to 86.1%) at the initial stage (from 0 min to 60 min) and increased gradually after 60 min with an adsorbent dosage of 105.2 g/L, pH of 5.6. The adsorption kinetics was well correlated with the pseudo-second-order equation. Removal of HPAM from the studied water samples indicated that steel slag can be utilised for the pre-treatment of polymer-flooding wastewater.

Optimization and Modeling of Microcystin-LR Degradation by TiO2 Photocatalyst Using Response Surface Methodology

Journal of Environmental Health and Sustainable Development ◽

10.18502/jehsd.v5i3.4278 ◽

2020 ◽

Author(s):

Negar Jafari ◽

Afshin Ebrahimi ◽

Karim Ebrahimpour ◽

Ali Abdolahnejad

Keyword(s):

Response Surface ◽

Removal Efficiency ◽

Contact Time ◽

High Performance ◽

Operating Variables ◽

Effective Removal ◽

Positive Effect ◽

Harmful Effects ◽

Maximum Removal

Introduction: Microcystin-leucine arginine (MC-LR) is a toxin with harmful effects on the liver, kidney, heart, and gastrointestinal tract. So, effective removal of MC-LR from water resources is of great importance. The aim of this study was to remove microcystin-LR (MC-LR) from aqueous solution by Titanium Dioxide (TiO2). Materials and Methods: In the present study, TiO2, as a semiconductor, was used for photodegradation of MC-LR under ultraviolet light (UV). The Response Surface Methodology was applied to investigate the effects of operating variables such as pH (A), contact time (B), and catalyst dose (B) on the removal of MC-LR. The MC-LR concentration was measured by high-performance liquid chromatography (HPLC). Results: The results showed that single variables such as A, B, and C had significant effects on MC-LR removal (pvalue < 0.05). In other words, increase of the contact time and catalyst dose had a positive effect on enhancing the removal efficiency of MC-LR, but the effect of pH was negative. The analysis of variance showed that BC, A2, and C2 variables had a significant effect on the MC-LR removal (pvalue < 0.05). Finally, the maximum removal efficiency of MC-LR was 95.1%, which occurred at pH = 5, contact time = 30 minutes, and catalyst dose = 1 g/l. Conclusion: According to the findings, TiO2, as a photocatalyst, had an appropriate effect on degradation of the MC-LR.

Multivariate Optimization of Pb2+ Adsorption onto Ethiopian Low-Cost Odaracha Soil Using Response Surface Methodology

Molecules ◽

10.3390/molecules26216477 ◽

2021 ◽

Vol 26 (21) ◽

pp. 6477

Author(s):

Yohanis Birhanu ◽

Seyoum Leta

Keyword(s):

Central Composite Design ◽

Response Surface ◽

Removal Efficiency ◽

Interaction Effect ◽

Contact Time ◽

Low Cost ◽

Design Model ◽

Lead Ions ◽

Experimental Result ◽

Lead pollution is a severe health concern for humankind. Utilizing water contaminated with lead can cause musculoskeletal, renal, neurological, and fertility impairments. Therefore, to remove lead ions, proficient, and cost-effective methods are imperative. In this study, the Odaracha soil which is traditionally used by the local community of the Saketa District was used as a novel low-cost technology to adsorb lead ions. Odaracha adsorbent was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The adsorption process followed the batch adsorption experiment. The response surface method was implemented to derive the operating variables’ binary interaction effect and optimize the process. According to the study’s experimental result, at optimum experimental conditions Odaracha adsorbent removes 98.17% of lead ions. Based on the result of the central composite design model, the Pb2+ ion removal efficiency of Odaracha was 97.193%, indicating an insignificant dissimilarity of the actual and predicted results. The coefficient of determination (R2) for Pb2+ was 0.9454. According to the factors’ influence indicated in the results of the central composite design model, all individual factors and the interaction effect between contact time and pH has a significant positive effect on lead adsorption. However, other interaction effects (contact time with dose and pH with dose) did not significantly influence the removal efficiency of lead ions. The adsorption kinetics were perfectly fitted with a pseudo-second-order model, and the adsorption isotherm was well fitted with the Freundlich isotherm model. In general, this study suggested that Odaracha adsorbent can be considered a potential adsorbent to remove Pb2+ ions and it is conceivable to raise its effectiveness by extracting its constituents at the industrial level.

ADSORPTION OF MALACHITE GREEN DYE USING SPENT COFFEE GROUND BIOCHAR: OPTIMISATION USING RESPONSE SURFACE METHODOLOGY

Jurnal Teknologi ◽

10.11113/jurnalteknologi.v83.14904 ◽

2020 ◽

Vol 83 (1) ◽

pp. 27-36

Author(s):

Mardawani Mohamad ◽

Rizki Wannahari ◽

Rosmawani Mohammad ◽

Noor Fazliani Shoparwe ◽

Kwan Wei Lun ◽

...

Keyword(s):

Adsorption Capacity ◽

Response Surface ◽

Malachite Green ◽

Contact Time ◽

Quadratic Model ◽

Adsorbent Dosage ◽

Coffee Grounds ◽

Spent Coffee Ground ◽

Coffee Ground

Used coffee grounds usually end up as landfill. However, the unique structural properties of its porous surface make coffee grounds can be transformed into biochar and performed as an alternative low cost adsorbent. Malachite green (MG) is a readily water soluble dye which is used extensively in textile and aquaculture industries. The mordant complex structures of MG generate destructive effects to animals and environment. In this study, adsorption of malachite green using spent coffee ground biochar as adsorbent was investigated. The experiments were designed in two methods: classical and optimisation by response surface methodology. Three parameters were studied, which are adsorbent dosage, contact time and pH while the responses in this study are malachite green removal (%) and adsorption capacity (mg/g). Optimisation studies were performed using response surface methodology. Quadratic model was chosen for both response and studied using central composite design. The correlation coefficient, R2 for the quadratic model of malachite green removal (%) and adsorption capacity (mg/g) were 0.95 and 0.99, respectively. The optimum malachite green removal (%) predicted was found at 99.27%, by using 0.12 g of adsorbent dosage, 43.05 minutes of contact time and pH of 9.45 at desirability of 1.0. The optimum adsorption capacity (mg/g) predicted was found at 118.01 mg/g, by using 0.02 g of adsorbent dosage, 60 minutes of contact time and pH of 10.24 at desirability of 0.98. So, it was concluded that the spent coffee ground biochar can be used as an effective adsorbent for malachite green removal from aqueous solution.

Development of compressed meat based bar using response surface methodology

Defence Life Science Journal ◽

10.14429/dlsj.2.11367 ◽

2017 ◽

Vol 2 (2) ◽

pp. 226

Author(s):

K. Jayathilakan ◽

Rajkumar Ahirwar ◽

Khudsia Sultana ◽

M. C. Pandey

Keyword(s):

Response Surface ◽

Applied Pressure ◽

Quadratic Model ◽

Central Composite Rotatable Design ◽

Protein Percentage ◽

Overall Acceptability ◽

Protein Levels ◽

Hedonic Scale ◽

Studies were carried out to optimize the percentage of ingredients for the development of ready to eat mutton bar. Central composite rotatable design of response surface methodology (RSM) was used for designing the experimental combinations. Matrix for compression was designed by selecting factors like mutton powder, binders and applied pressure. Protein percentage, hardness and over all acceptability (OAA) were taken as responses. OAA and hardness showed highly significant and fitted with quadratic model whereas other response i.e. protein levels found to be significant and fitted with linear model. From the design of experiments 45g/100g of mutton powder with 5g/100g binders having an applied pressure of 142 kg/cm2 yielded a bar having a protein percentage of 35g/100g with a hardness of 20.9 N with an overall acceptability score of 8.6 ±0.2 on a 9 point hedonic scale. The product gives energy of 393 kcal per 100 g.

Design and Optimization of a Process for Sugarcane Molasses Fermentation bySaccharomyces cerevisiaeUsing Response Surface Methodology

International Journal of Microbiology ◽

10.1155/2013/815631 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 24

Author(s):

Nour Sh. El-Gendy ◽

Hekmat R. Madian ◽

Salem S. Abu Amr

Keyword(s):

Response Surface ◽

Batch Fermentation ◽

Fermentation Process ◽

Incubation Temperature ◽

Operating Conditions ◽

Quadratic Model ◽

Optimum Operating ◽

Sugarcane Molasses ◽

Bioethanol Production

A statistical model was developed in this study to describe bioethanol production through a batch fermentation process of sugarcane molasses by locally isolatedSaccharomyces cerevisiaeY-39. Response surface methodology RSM based on central composite face centered design CCFD was employed to statistically evaluate and optimize the conditions for maximum bioethanol production and study the significance and interaction of incubation period, initial pH, incubation temperature, and molasses concentration on bioethanol yield. With the use of the developed quadratic model equation, a maximum ethanol production of 255 g/L was obtained in a batch fermentation process at optimum operating conditions of approximately 71 h, pH 5.6, 38°C, molasses concentration 18% wt.%, and 100 rpm.

Extraction of Flavonoids from Clovers

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.195-196.360 ◽

2012 ◽

Vol 195-196 ◽

pp. 360-363

Author(s):

Chun Gang Chen ◽

Fen Xia Han ◽

Yuan Zhang ◽

Yu Zhong Shi

Keyword(s):

Optimum Condition ◽

Central Composite Design ◽

Response Surface ◽

Ethanol Concentration ◽

Response Surfaces ◽

Second Order ◽

Order Model ◽

Solid Ratio ◽

The extraction of flavonoids from clovers was optimized to maximize flavonoid yield Y in this study. A central composite design of response surface methodology involving extracting time, liquid-solid ratio, extracting temperature and ethanol concentration was used, and second-order model for Y was employed to generate the response surfaces. The optimum condition for Y was determined as follows: extracting time 24min, liquid-solid ratio 20, extracting temperature 80°C, and ethanol concentration 72%. Under the optimum condition, the flavonoid yield was 2.49%.

Application of Electrocoagulation for the Removal of Color from Institutional Wastewater: Analysis with Response Surface Methodology

Journal of Environmental Treatment Techniques ◽

10.47277/jett/9(2)479 ◽

2021 ◽

Vol 9 (2) ◽

pp. 470-479

Keyword(s):

Reaction Time ◽

Response Surface ◽

The Other ◽

Quadratic Model ◽

Operational Parameters ◽

Electrode Combination ◽

Electrocoagulation Process ◽

Percentage Removal ◽

The removal percentage of color from institutional wastewater was studied using an electrocoagulation process with different electrode combination at the anode and cathode. This was done by considering operational parameters such as pH at (3, 6 and 9), current at (0.03A, 0.06A and 0.09A) and reaction time at (20, 40 and 60 minutes). When electrode combined in the form of Al-Al (anode-Cathode/Cathode-Anode) and Fe-Fe (anode-Cathode/Cathode-Anode) the percentage removal of color was up to 95.50% and 97.24% respectively. On the other hand around 98.03% and 91.95% of color was removed when Al-Fe (Anode-Cathode) and Fe-Al (Anode-Cathode) combined at pH 9 and 60 minutes of reaction time respectively. Central composite design from response surface methodology was used up to analysis the statistical and mathematical data based on experimental results such as the model was significant for all electrode combinations. Similarly a quadratic model was used for further study of operational effects on the removal (%) of color from institutional wastewater. The value of coefficient of the determination (R2) also indicated the model was a good fit as well as optimization was done by Response Surface Methodology.

Optimisation of Tray Drier Microalgae Dewatering Techniques Using Response Surface Methodology

Energies ◽

10.3390/en11092327 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2327 ◽

Cited By ~ 7

Author(s):

Ruth Anyanwu ◽

Cristina Rodriguez ◽

Andy Durrant ◽

Abdul Olabi

Keyword(s):

Response Surface ◽

Air Temperature ◽

Operating Conditions ◽

Optimum Operating ◽

Slight Effect ◽

Air Velocity ◽

Independent Variables ◽

Air Supply ◽

The feasibility of the application of a tray drier in dewatering microalgae was investigated. Response surface methodology (RSM) based on Central Composite Design (CCD) was used to evaluate and optimise the effect of air temperature and air velocity as independent variables on the dewatering efficiency as a response function. The significance of independent variables and their interactions was tested by means of analysis of variance (ANOVA) with a 95% confidence level. Results indicate that the air supply temperature was the main parameter affecting dewatering efficiency, while air velocity had a slight effect on the process. The optimum operating conditions to achieve maximum dewatering were determined: air velocities and temperatures ranged between 4 to 10 m/s and 40 to 56 °C respectively. An optimised dewatering efficiency of 92.83% was achieved at air an velocity of 4 m/s and air temperature of 48 °C. Energy used per 1 kg of dry algae was 0.34 kWh.

Useful Numerical Statistics of Some Response Surface Methodology Designs

Journal of Mathematics Research ◽

10.5539/jmr.v8n4p40 ◽

2016 ◽

Vol 8 (4) ◽

pp. 40

Author(s):

Iwundu M. P.

Keyword(s):

Response Surface ◽

Optimality Criteria ◽

Second Order ◽

First Order ◽

Central Composite Designs ◽

Alphabetic Optimality ◽

Main Effects ◽

Composite Designs ◽

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.