Biodiesel production using alkaline ionic liquid and adopted as lubricity additive for low-sulfur diesel fuel

► [Bmim]Im was applied in the transesterification of vegetable oils with methanol. ► [Bmim]Im exhibited high activity under mild reaction conditions. ► The catalytic performance of [Bmim]Im remained excellent after reused many times. ► An increase in unsaturation of biodiesel leads to a higher lubrication performance.