Tetramethylguanidine covalently bonded onto silica gel surface as an efficient and reusable catalyst for transesterification of vegetable oil

Optimization of operating conditions for separation of non polar lipids fraction from soybean oil deodorizer distillate by regenerated silica gel

“…It can be seen that a large broad band between 3200 and 3400 cm -1 was assigned to the presence of the O-H stretching frequency of silanol groups and also to the remaining adsorbed water, a band around 1650 cm -1 was assigned to the angular vibration of water molecules, an intense band at 1100 cm -1 was related to the siloxane stretching (Si-O-Si), and a band at 900 cm -1 was assigned to the Si-OH stretching frequency of silanol groups. These assignments agree with previous observation on the nature of silica surface [15,16]. Furthermore, the surface roughness charateristics of fresh and regenerated silica gels are qualitatively explored by SEM as shown in Figure 3 and 4.…”

Cocrystals of Kemp’s triacid. Part III: Structure of hydrogen-bonded complex of Kemp’s triacid with 1,1,3,3-tetramethylguanidine studied by X-ray and FT-IR methods

“…TMG is a strong N-base (pK a = 23.3) [19] which has been effectively used for a variety of base-mediated organic transformations [20][21][22] and is also commonly used in various deprotonation reactions [23,24].…”

Sodium phosphate as a solid catalyst for biodiesel preparation

“…Many solid bases have been reported to transesterify triglyceride, such as alkaline earth oxides (Corma et al 2006, Kouzu et al 2008, Liu et al 2008, anion exchange resin (Shibasaki-Kitakawa et al 2007), organic solid base (Faria et al 2008, de Rezende et al 2008, supported solid base (Samart et al , Verziu et al 2009). Recently, many types of alkali metal compounds have been employed for biodiesel preparation: biodiesel was produced from soybean oil over sodium aluminate; the solid base showed high catalytic activity for methanolysis, reaching a 93.6% yield under optimal reaction conditions, and the reaction contained homogeneous and heterogeneous contributions at the same time (Tao Wan et al 2009); Arzamendi et al (2008) reported that sodium, potassium carbonate and sodium phosphate all catalyzed transesterification; potassium carbonate had the highest activity, while sodium carbonate and sodium phosphate exhibited almost the same activity which was much lower than potassium carbonate.…”