scholarly journals Optimisation Of Process Parameters In High Energy Mixing As A Method Of Cohesive Powder Flowability Improvement

2015 ◽  
Vol 36 (4) ◽  
pp. 449-460 ◽  
Author(s):  
Karolina Leś ◽  
Karol Kowalski ◽  
Ireneusz Opaliński

Abstract Flowability of fine, highly cohesive calcium carbonate powder was improved using high energy mixing (dry coating) method consisting in coating of CaCO3 particles with a small amount of Aerosil nanoparticles in a planetary ball mill. As measures of flowability the angle of repose and compressibility index were used. As process variables the mixing speed, mixing time, and the amount of Aerosil and amount of isopropanol were chosen. To obtain optimal values of the process variables, a Response Surface Methodology (RSM) based on Central Composite Rotatable Design (CCRD) was applied. To match the RSM requirements it was necessary to perform a total of 31 experimental tests needed to complete mathematical model equations. The equations that are second-order response functions representing the angle of repose and compressibility index were expressed as functions of all the process variables. Predicted values of the responses were found to be in a good agreement with experimental values. The models were presented as 3-D response surface plots from which the optimal values of the process variables could be correctly assigned. The proposed, mechanochemical method of powder treatment coupled with response surface methodology is a new, effective approach to flowability of cohesive powder improvement and powder processing optimisation.

Author(s):  
Abed Saad ◽  
Nour Abdurahman ◽  
Rosli Mohd Yunus

: In this study, the Sany-glass test was used to evaluate the performance of a new surfactant prepared from corn oil as a demulsifier for crude oil emulsions. Central composite design (CCD), based on the response surface methodology (RSM), was used to investigate the effect of four variables, including demulsifier dosage, water content, temperature, and pH, on the efficiency of water removal from the emulsion. As well, analysis of variance was applied to examine the precision of the CCD mathematical model. The results indicate that demulsifier dose and emulsion pH are two significant parameters determining demulsification. The maximum separation efficiency of 96% was attained at an alkaline pH and with 3500 ppm demulsifier. According to the RSM analysis, the optimal values for the input variables are 40% water content, 3500 ppm demulsifier, 60 °C, and pH 8.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 182
Author(s):  
Kang Hyun Lee ◽  
Ye Won Jang ◽  
Hansol Kim ◽  
Jang-Seu Ki ◽  
Hah Young Yoo

Microalgae have been attracting attention as feedstock for biorefinery because they have various advantages, such as carbon fixation, high growth rate and high energy yield. The bioactive compounds and lutein contained in microalgae are known to be beneficial for human health, especially eye and brain health. In this study, in order to improve the recovery of bioactive extracts including lutein from Tetraselmis suecica with higher efficiency, an effective solvent was selected, and the extraction parameters such as temperature, time and solid loading were optimized by response surface methodology. The most effective solvent for lutein recovery was identified as 100% methanol, and the optimum condition was determined (42.4 °C, 4.0 h and 125 g/L biomass loading) by calculation of the multiple regression model. The maximum content of recovered lutein was found to be 2.79 mg/mL, and the ABTS radical scavenging activity (IC50) and ferric reducing antioxidant power (FRAP) value were about 3.36 mg/mL and 561.9 μmol/L, respectively. Finally, the maximum lutein recovery from T. suecica through statistical optimization was estimated to be 22.3 mg/g biomass, which was 3.1-fold improved compared to the control group.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3150
Author(s):  
Mengwei Xu ◽  
Chao Huang ◽  
Jing Lu ◽  
Zihan Wu ◽  
Xianxin Zhu ◽  
...  

Magnetic MXene composite Fe3O4@Ti3C2 was successfully prepared and employed as 17α-ethinylestradiol (EE2) adsorbent from water solution. The response surface methodology was employed to investigate the interactive effects of adsorption parameters (adsorption time, pH of the solution, initial concentration, and the adsorbent dose) and optimize these parameters for obtaining maximum adsorption efficiency of EE2. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. Optimization of the process variables for maximum adsorption of EE2 by Fe3O4@Ti3C2 was performed using the quadratic model. The model predicted maximum adsorption of 97.08% under the optimum conditions of the independent variables (adsorption time 6.7 h, pH of the solution 6.4, initial EE2 concentration 0.98 mg L−1, and the adsorbent dose 88.9 mg L−1) was very close to the experimental value (95.34%). pH showed the highest level of significance with the percent contribution (63.86%) as compared to other factors. The interactive influences of pH and initial concentration on EE2 adsorption efficiency were significant (p < 0.05). The goodness of fit of the model was checked by the coefficient of determination (R2) between the experimental and predicted values of the response variable. The response surface methodology successfully reflects the impact of various factors and optimized the process variables for EE2 adsorption. The kinetic adsorption data for EE2 fitted well with a pseudo-second-order model, while the equilibrium data followed Langmuir isotherms. Thermodynamic analysis indicated that the adsorption was a spontaneous and endothermic process. Therefore, Fe3O4@Ti3C2 composite present the outstanding capacity to be employed in the remediation of EE2 contaminated wastewaters.


2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Libo Zhang ◽  
Wenqian Guo ◽  
Tu Hu ◽  
Jing Li ◽  
Jinhui Peng ◽  
...  

AbstractThe process of microwave drying ammonium tetramolybdate is studied, and the process variables of drying time, drying temperature and material thickness are considered. Experiences of microwave drying ammonium tetramolybdate have been optimized using response surface methodology (RSM) technique and a CCD design. Effects of each factor and their interactions are researched, and a quadratic polynomial model for dehydration ratio is established. As can be seen from the ANOVA, the effects of the three process variables are found to be significant in the model, and the empirical model is fit and reliable to check the dehydration ratio of ammonium tetramolybdate. The optimum conditions for drying using microwave heating are found as follows: drying temperature 67°C, drying time 9.5 min and material thickness 15 mm. The optimum dehydration ratio is 79.82% and the last molybdenum content is not <56.3%, with the relatively error of 0.64%, which indicates the success of the process optimization experiments. This research has important significance to offer optimum conditions for industrial production.


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