Conversion of Au(Ⅲ)-polluted waste eggshell into functional CaO/Au nanocatalyst for biodiesel production

摘要

Developing an environmental-friendly and highly active catalyst in transesterification for biodiesel production is of great importance for a more economic biodisel process.Herein,we reported that waste eggshells were used to adsorb Au(Ⅲ) in water and convert the Au(Ⅲ)-polluted eggshells into the functional nanocatalyst-Ca O/Au for the transesterification reaction between soybean oil and methanol to the preparation of biodiesel.By coupling of Ca O and Au nanoparticles,Ca O/Au nanoparticles showed superior catalytic activity for the transesterification reaction between soybean oil and methanol.An optimum performance was observed over Ca O/Au nanocomposites in a methanol-oil molar ratio at 12:1with catalyst content of 1.0 wt% at 70°C for 3 h.Besides,the catalytic activity of Ca O/Au nanocatalyst was almost unchanged after recycling for 5 times and the yield of biodiesel still kept at 88.9%.The proof-of concept study provided us a sustainable method for utilization of waste eggshells to remedy the metal ions-polluted wastewater and the synthesis of functional nanocomposite for biodiesel production,show great potential application of waste eggshell in adsorption and catalytic reactions.