Developing sustainable strategies for biodiesel synthesis using high fatty acid feedstock

Authors: Ngo, Helen; ZAFIROPOULOS, NICHOLAS - University Of North Carolina; Foglia, Thomas; SAMULSKI, EDWARD - University Of North Carolina; LIN, WENBIN - University Of North Carolina

Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/12/2009
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Biodiesel (typically fatty acid methyl esters (FAME)) has received much attention because it is a renewable biofuel that contributes little to global warming compared to petroleum-based diesel fuel. The most common methods used for biodiesel production are based on the alkali-catalyzed transesterification of first-use refined oils and fats. These technologies, however, require significant modification when applied to second use materials such as greases because of their higher free fatty acid (FFA) content. Recently, we reported a series of insoluble porous polymer grafted diphenylammonium salts that efficiently esterified the FFA in greases to FAME. The treated greases with low concentration of FFA (<1 wt%) could then be successfully converted to FAME in the presence of sodium methoxylate. In this presentation, I will discuss our efforts on immobilizing the diphenylammonium salts on two robust mesoporous silicas. The resulting heterogeneous catalysts had high esterification activity: > 99% of the FFA in greases was esterified to FAME, which reduced the FFA content in the treated greases to < 1 wt% with only minimal transesterification activity.