Effect of the Acid Treatment of Montmorillonite Clay in the Oleic Acid Esterification Reaction

Biodiesel is a fuel renewable, biodegradable and environmentally correct fuel, which can be obtained from the esterification reactions, transesterification and pyrolisis. Montmorillonite is a clay mineral of the smectite group and are of great interest for industrial processes such as catalysis and adsorption. Acid activation of clay minerals is one of the most effective methods proposed to produce active materials. In this work, montmorillonite clay was treated with H₂SO₄ in different concentrations (0.2 – 0.8 mol L^–1), characterized by X-ray diffraction (XRD), infrared spectroscopy (FT-IR) and applied in the catalytic esterification of oleic acid. The results reveal that the clay treated with aqueous solutions 0.8 mol L^–1 H₂SO₄ shows promising catalytic activity toward the studied reaction, with maximum conversion of oleic acid of 65% at 30 °C.

montmorillonite clay; acid treatement; esterification; oleic acid; biofuel