Separation of mixtures of fatty acids into individual components using a nanoporous membrane

A. Gupta, N.B. Bowden
University of Iowa, US

Keywords: fatty acids, vegetable oils, nanoporous, membrane


We recently developed the first method to separate fatty acids derived from vegetable oils using nanoporous membranes based on polydicyclopentadiene. Fatty acids were too small and too similar in size to be separated from one another using nanoporous membranes, but when an amine was added the fatty acid/amine salts were large enough and had different sizes such that they could be separated from one another. This work describes a new, exciting method to employ an organic solvent nanofiltration membrane to solve a key problem in industry. Furthermore, because the separation requires an amine to coordinate to the fatty acids and numerous amines with different sizes are available or easily synthesized, it is straightforward to optimize the separation of mixtures of fatty acids by investigating the effect of different amines. The key problem that is addressed in this research is how to separate mixtures of fatty acids into individual, pure fatty acid components. Over 140 million tons of vegetable oils are produced each year, but their fatty acids are used in very few industrial processes due to the high cost of pure fatty acids. Separations based on membranes are inexpensive and can be used to separate large quantities.