Waste Cooking Oil Conversion to Biodiesel Using Solid Bifunctional Catalysts

The draining of fossil fuels and their toxic influence on the environment has prompted the need for alternative fuels known as biofuels. Of the various types of biofuel, biodiesel has attracted wide interest in the world today since it promotes carbon neutrality. The transesterification and interesterification process remains the most widely used process route for biodiesel production. In this review, the performance efficiency of solid base, solid acid, and bifunctional solid acid-base catalysts for biodiesel production from waste cooking oil is considered. In particular, the benefit of exploring the biomass-derived acid-base heterogeneous bifunctional catalysts, current status, and future prospects for biodiesel production from waste cooking oil are elucidated.