Transforming animal fats into biodiesel using charcoal and CO2

Abstract

This paper presents a simple methodology for producing biodiesel. This study confirmed that the main driving force of biodiesel conversion through the non-catalytic transesterification reaction is temperature rather than pressure. Non-catalytic biodiesel conversion can be achieved in the presence of a porous material via a thermochemical process and a real continuous flow system. In addition, this non-catalytic conversion of biodiesel can be enhanced by the presence of carbon dioxide (CO₂). In particular, in this work, the transformation of animal fat (beef tallow and lard) into biodiesel was achieved using charcoal and CO₂ under ambient pressure. This newly introduced methodology for producing biodiesel combines esterification of free fatty acids and transesterification of triglycerides into a single process and leads to a 98.5 (±0.5)% conversion efficiency of biodiesel within 1 min at 350–500 °C. The new process has high potential to achieve a breakthrough in minimizing the cost of biodiesel production owing to its simplicity and technical advantages.