Biodiesel Preparation from Soybean Oil by Using a Heterogeneous CaxMg2−xO2 Catalyst

Abstract

An effective heterogeneous catalyst, Ca x Mg 2-x O 2 , was prepared and tested for soybean oil transesterification with methanol. The catalysts were characterized by using X-ray diffraction , Fourier transform infrared spectra, thermo gravimetric and differential thermal analysis , and Hammett indicator method. The catalyst with Ca/Mg ratio of 1.0 and calcined at 800°C exhibited high catalytic activities. Under the suitable transesterification conditions (methanol/oil ratio 12:1, catalyst loading 6 wt%, reaction time 5 h, at reflux of methanol), the oil conversion of 91.3% could be achieved. The catalyst can be easily recovered and reused without significant deactivation.

Highly active and durable Ca-doped Ce-SBA-15 catalyst for biodiesel production

“…The low total basicity of the CaOeCeO 2 /SBA-15 catalyst is mainly resulted from the agglomeration of CaO and CeO 2 , forming the CaO and CeO 2 clusters on the SBA-15 support which can be evidenced by the sharp diffraction XRD peaks of CaO, Ca(OH) 2 , and CeO 2 , as previously discussed. The agglomeration of CeO 2 , CaO and Ca(OH) 2 not only lower the area of the active sites for the reaction, but also leads to the difficulty of the bulky reactants to access the active sites [39,56]. Fig.…”

The stability evaluation of lime mud as transesterification catalyst in resisting CO2 and H2O for biodiesel production

“…According to the reported literature, the catalytic activity could be enhanced with higher basicity [10]. It is speculated that except for the predominant compound of CaO in the LM700, impurities such as Na 2 O, SiO 2 , MgO and Al 2 O 3 also made the synergistic effect to catalytic activity.…”

“…The indicators used in this study include bromthymol blue Table 1 The fatty acids constituents of triglycerides for peanut oil, used peanut oil and palm oil. [10]. Microstructure parameters of the catalyst are obtained on 2020 surface area and porosity analyzer (Micromeritics Co., Ltd, USA) through nitrogen adsorption at 77 K. Prior to the analysis, all catalysts are degassed at 300°C for 5 h to desorb the volatiles from the surface.…”

“…[1,2]. Chemically, biodiesel is a mixture of fatty acid methyl esters (FAME) normally obtained by transesterification under the catalytic effect of bases, acids or enzymes [3][4][5][6][7][8][9][10]. Calcium oxide (CaO), a representative and promising heterogeneous base catalyst, has been adopted in transesterification for its abundant availability, environmental friendliness and high catalytic activity [6,7].…”

Influence of calcination temperature on the activity of mesoporous CaO/TiO2–ZrO2 catalyst in the esterification reaction

“…With increasing calcination temperature up to 400 °C, the peaks at 1300-1400 cm −1 which were assigned to the asymmetric and strong stretching vibrations of NO 3 ions disappeared, providing additional evidence for transformation of the sample from amorphous to crystal form and higher activity of calcined catalysts over 300 °C. The band that appeared at 1420 cm −1 is attributed to the carbonate groups due to adsorption of CO 2 on the catalyst surface [42]. The peak at 1600-1680 cm −1 belongs to (-C=O) stretching vibration from citric acid and also may be bending vibration of H 2 O molecules which overlapped and cannot be observed with increasing calcination temperature.…”