Driven by the high energy demand and environmental concerns, biodiesel as a substitute for fossil fuels is recognized as promising renewable and clean energy. Biodiesel has gained interest around the world over the last few years because it could be used to reduce most regulated exhaust emissions. Herein, we discuss the application of catalytic transesterification by using ionic liquids (ILs) catalyst with alcohol and waste oil for the clean synthesis of biodiesel in order to reduce the emission of NO_x and CO. However, the running cost of this process is still higher than that of the conventional chemical transesterification. Non-edible sources such as waste oil, non-edible vegetable oil, and waste animal oil are commonly used to produce biodiesel due to their low cost and no dependency on the food chain. This review provides an overview of the recent progresses in improving the biodiesel production process by using ILs and determining the activation energy and the properties of the finished product. In addition, the future direction in biodiesel production via ILs catalysis in the transesterification has been discussed.

在高能源需求和环境问题的推动下，生物柴油作为化石燃料的替代品被公认为有前途的可再生清洁能源。在过去的几年里，生物柴油在世界范围内引起了人们的兴趣，因为它可以用来减少大多数受管制的废气排放。在此，我们讨论了使用离子液体（ILs）催化剂与酒精和废油进行催化酯交换在生物柴油清洁合成中的应用，以减少 NO _x的排放。但是，该工艺的运行成本仍高于传统的化学酯交换。地沟油、非食用植物油和废弃动物油等非食用来源由于成本低且不依赖食物链，因此通常用于生产生物柴油。本综述概述了通过使用 IL 和确定活化能和成品的特性来改进生物柴油生产过程的最新进展。此外，还讨论了酯交换中通过 ILs 催化生产生物柴油的未来方向。