Effects of Molar Ratio on Triacylglycerol Conversion in Glycerolysis Using Sodium Metasilicate and MgO Catalysts in a High Shear Compartment Reactor

This research examines the influence of different molar ratios on the conversion of triacylglycerol (TAG) to monoglycerides (MAG) and diglycerides (DAG) in a solvent-free glycerolysis reaction conducted within a high shear compartment reactor. The reaction was catalyzed using a combination of sodium metasilicate and MgO at 120°C with a stirring speed of 1500 rpm. The highest TAG conversion was observed at a PKO to glycerol ratio of 1:3, yielding 56.96±3.39 MAG and DAG. However, increasing the glycerol content resulted in higher product viscosity, reaching up to 26.20±1.56 mPa.s on the MDAG product with a molar ratio of 1:5. Additionally, the lightness (L∗ value) of the liquid MDAG product increased with higher glycerol content, with a maximum L∗ value of 56.63 observed. An excessive glycerol ratio also increased the free glycerol in the MDAG product, with the highest level recorded at a 1:4 molar ratio, measuring 3.55±0.36. These findings suggest that while a 1:3 PKO to glycerol ratio is optimal for maximizing TAG conversion, further increases in glycerol content may adversely affect product quality by increasing viscosity and free glycerol levels. © Published under licence by IOP Publishing Ltd.