Tribological evaluation of rice bran oil based ionanolubricants containing ionic liquids and nanoparticles

Abstract

ABSTRACT Environmental concerns and depleting mineral oil resources have forced us to develop environmentally acceptable lubricants. In this study, tribological properties of rice bran oil containing imidazolium-based ionic liquid 1- ethyl 3methylimidazolium dicyanamide ([EMIM][DCN]) (ILa), phosphonium based ionic liquid Trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ([P66614][BTMPP]) (ILb) and titanium oxide (TiO2) nanoparticles (NPs) as hybrid additives have been investigated using four ball tester. Rice bran oil based ionanolubricants (INLs) were formulated with different concentrations of ILa, ILb and TiO2 NPs. Among all investigated ionanolubricant samples, rice bran oil containing 0.03 of TiO2 NPs and 0.5 vol.% of ILa showed the lowest AWSD. The improved characteristics of rice bran oil based INLs can be attributed to the ball bearing effect and tribofilm formation. GRAPHICAL ABSTRACT