Nanoclays as dispersing precursors of La and Ce oxide catalysts to produce high-valued derivatives of biodiesel by-product

Abstract

Hydrotalcite-like compounds are valuable anionic nanoclays due to their functionalized capacity. Rare earth elements, La and Ce, were incorporated in those materials by co-precipitation and wet impregnation methods. The materials were calcined and used as mixed oxides in the selective production of monoglycerides at 220 °C and with a glycerol/methyl stearate molar ratio of 6:1. Catalysts were characterized by X-ray diffraction, surface area, scanning electron microscopy, inductively coupled plasma − optical emission spectroscopy, temperature-programmed desorption, and X-ray photoelectron spectroscopy. The product yield was determined by gas chromatography with flame ionization detector. The catalyst structural surface properties and basicity were determined by the composition of the mixed oxides, as was revealed by the catalytic behavior of the materials. The sample with Ce incorporated by the impregnation method exhibited the highest basicity, which is probably related to the highest monoglyceride yield of 77%.