Tribological properties and thermal-stability of epoxide-functionalized biolubricant derived from the abandon aerial part of Codonopsis pilosula

Stringent environment concern, petroleum reserves depletion and circular economy drive the demand for high performance bio-lubricants from the agro-waste, but poor thermal stability is the main obstacle limiting its application. This study develops a green and mild epoxidation route to improve the thermal stability of the biomass oil from the abandon aerial part of Codonopsis pilosula. The reaction was carried out at room temperature with manganese complex as catalyst and in situ formed peracetic acid as oxidant, obtaining epoxy yield of 65% in two hours. The thermal stability of the Codonopsis pilosula oil increases from 234° to 311°C via epoxidation modification, and the lubricating performances are comparable before and after the chemical modification.