Optimization of Salix Carbonation Solid Acid Catalysts for One-Step Synthesis by Response Surface Method

Abstract

Salix carboniferous solid acid catalysts were successfully obtained via one-step carbonization and sulfonation of Salix psammophila in the presence of concentrated sulfuric acid, which was then used in the esterification reaction between oleic acid and methanol to prepare the biodiesel. The esterification rate of the catalyst obtained from the reaction indicated the catalytic performance of the catalyst. Afterwards, the recycling performance of the catalyst was optimized and characterized based on Fourier transform infrared spectrometer. The catalyst performance was examined and optimized through the response surface method, and the catalyst was determined and characterized based on scanning electron microscope (SEM), elemental analysis, thermogravimetric analysis, and infrared analysis. The results suggested that the optimal preparation conditions were as follows: reaction temperature of 125 °C, reaction time of 102 min, solid–liquid ratio of 17 g/100 mL, standing time of 30 min, and the highest conversion level of 94.15%.

Synthesis of 2-Ethyl-3-oxazolidineethanol from Propanal and Diethanolamine: Kinetic and Process Optimization Study

“…The proposed response surface regression model reached a significant level, P = 0.0001 < 0.05; however, the lack of fit was P = 0.1856 > 0.05, which was not significant, indicating that the model is not significant relative to the absolute error. The regression equation does not lack fit and can be used for research on the synthesis process of OE. , …”

“…A 3D graphic can describe the characteristics of response surface function and visually show how different elements interact to affect the response value . The shape of the contour line can be used to determine the strength of the interaction effect.…”

“…The regression equation does not lack fit and can be used for research on the synthesis process of OE. 42,44 According to the regression equation analysis of variance, the first-order terms of temperature and molar ratio, as well as the quadratic terms of temperature, time, and PA/DEA molar ratio, had a significant impact on the synthesis of OE. In the linear term, the PA/DEA molar ratio (C) has the greatest impact, P < 0.0001.…”

“…A 3D graphic can describe the characteristics of response surface function and visually show how different elements interact to affect the response value. 44 The shape of the contour line can be used to determine the strength of the interaction effect. As illustrated in Figure 8, the twodimensional (2D) contour plots and three-dimensional (3D) response surface plots response against the variables were used to illustrate the interaction between independent and dependent factors.…”

Special Issue on New Carbon Materials from Biomass and Their Applications

“…Biomass-derived carbons are also being extensively analyzed as part of catalysts and/or catalyst's support in different catalytic reactions. Lu et al [14] synthesized solid acid catalysts by one-step carbonization and sulfonation of Salix psammophila in the presence of concentrated sulfuric acid. The catalysts were used in the esterification reaction between oleic acid and methanol to prepare the biodiesel, achieving a conversion of 94.15% in the optimized conditions.…”