scholarly journals Investigation of the Process Conditions for Hydrogen Production by Steam Reforming of Glycerol over Ni/Al2O3 Catalyst Using Response Surface Methodology (RSM)

Materials ◽  
2014 ◽  
Vol 7 (3) ◽  
pp. 2257-2272 ◽  
Author(s):  
Ali Ebshish ◽  
Zahira Yaakob ◽  
Yun Taufiq-Yap ◽  
Ahmed Bshish
2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Yingpeng Tong ◽  
Yu Jiang ◽  
Dan Guo ◽  
Yongqiu Yan ◽  
Shiping Jiang ◽  
...  

Saffron, which has many kinds of biological activities, has been widely used in medicine, cosmetics, food, and other fields of health promotion industries. Crocins are the main component of saffron (Crocus sativus L.). At present, most of the extraction methods for crocins require long time or special instruments to complete the process and some of them are not suitable for industrial production at present. In this article, homogenate extraction technology which is a convenient and efficient method was developed for crocins extraction from saffron. Firstly, the influences of extraction voltage, extraction time, ethanol concentration, and temperature on crocins yield were studied by single factor experiments; and then response surface methodology (RSM) was used to optimize levels of four variables based on the result of single factor experiments. Results showed that the optimum extraction process conditions for crocins were as follows: extraction voltage, 110 V; ethanol concentration, 70%; extraction temperature, 57°C; and extraction time, 40 s. Based on these conditions, the extraction yield of crocins can reach 22.76% which is higher than ultrasonic extraction method. Therefore, homogenate extraction is an effective way to extract crocins from saffron with higher extraction yield and shorter extraction time.


2021 ◽  
Vol 132 (2) ◽  
pp. 907-919
Author(s):  
O. Shtyka ◽  
Z. Dimitrova ◽  
R. Ciesielski ◽  
A. Kedziora ◽  
G. Mitukiewicz ◽  
...  

AbstractEthanol steam reforming was studied over Ni supported catalysts. The effects of support (Al2O3, Al2O3–ZnO, and Al2O3–CeO2), metal loading, catalyst activation method, and steam-to-ethanol molar feed ratio were investigated. The properties of catalysts were studied by N2 physisorption, TPD-CO2, X-ray diffraction, and temperature programmed reduction. After activity tests, the catalysts were analyzed by TOC analysis. The catalytic activity measurements showed that the addition either of ZnO SSor CeO2 to alumina enhances both ethanol conversion and promotes selectivity towards hydrogen formation. The same effects were observed for catalysts with higher metal loadings. High process temperature and high water-to-ethanol ratio were found to be beneficial for hydrogen production. An extended catalyst stability tests showed no loss of activity over 50 h on reaction stream. The TOC analysis of spent catalysts revealed only insignificant amounts of carbon deposit.


2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Teresa Delgado ◽  
Bruna Paim ◽  
José Alberto Pereira ◽  
Susana Casal ◽  
Elsa Ramalhosa

Osmotic dehydration of chestnut slices in sucrose was optimized for the first time by Response Surface Methodology (RSM). Experiments were planned according to a three-factor central composite design (α=1.68), studying the influence of sucrose concentration, temperature and time, on the following parameters: volume ratio, water activity, color variation, weight reduction, solids gain, water loss and normalized moisture content, as well as total moisture, ash and fat contents. The experimental data was adequately fitted into second-order polynomial models with coefficients of determination (R2) from 0.716 to 0.976, adjusted-R2 values from 0.460 to 0.954, and non-significant lacks of fit. The optimal osmotic dehydration process conditions for maximum water loss and minimum solids gain and color variation were determined by the “Response Optimizer” option: 83% sucrose concentration, 20 °C and 9.2 hours. Thus, the best operational conditions corresponded to high sugar concentration and low temperature, improving energy saving and decreasing the process costs.


2019 ◽  
Vol 79 (11) ◽  
pp. 2046-2055
Author(s):  
Shengjian Li ◽  
Ting Lei ◽  
Fang Jiang ◽  
Changlin Miao ◽  
Xiangjun Yang ◽  
...  

Abstract The purpose of this study was to optimize the coagulation–flocculation effect of a wastewater treatment system using the response surface methodology (RSM) and three-step method to minimize phosphorus concentration in the distillate wastewater. In order to minimize the concentration of total phosphorus (TP), experiments were carried out using -factorial designs with three levels and three factors. A Box–Behnken design, which is the standard design of RSM, was used to evaluate the effects and interactions of three major factors (Fe:P (w/w) ratio, coagulation pH and fast mixing speed (FMS)) on the treatment efficiency. A multivariable quadratic model developed for studying the response indicated that the values for optimum conditions for Fe:P (w/w) ratio, coagulation pH and FMS were 2.40, 6.48 and 100 rev min−1, respectively. Under optimal process conditions, the TP concentration in the distillery effluent was reduced from 10 mg L−1 to 0.215 mg L−1, representing a removal efficiency of 97.85%. Based upon the statistical evaluation of results, it is inferred that RSM can be used as an appropriate approach to optimize the coag-flocculation process. Meanwhile, the study has shown that, for the equivalent dose of ferric chloride, the average three-step effect is better than that of the one-time addition.


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