Full biodiesel yield by enzymatic transesterification

Abstract: Production of biodiesel using a liquid lipase is well known and employed industrially. The enzymatic process today is primarily applied for the waste oils segment of the market, where free fatty acid (FFA) levels are typically high. FFA complicates the chemical methoxide process, while the enzymatic process can react regardless of FFA levels. 1-7 wt% FFA remains after today's enzymatic reaction depending on feedstock quality. The biodiesel specifications in both the US and EU requires FFA < 0.25 wt% and the residual FFA of the enzymatic process must therefore be addressed in post-processing, typically through soap stock formation, which is the current main drawback of the enzymatic process. In this presentation we will discuss the latest developments in process technology and present data on how to run a single enzymatic reaction capable of fully converting glycerides of crude vegetable oils to FAME while simultaneously reaching < 0.25 wt% FFA without post treatment. This is a major improvement and makes the enzymatic biodiesel process a viable green and suitable alternative to the chemical methoxide process.