Removal of free fatty acid from crude palm oil using organic solvent nanofiltration (OSN)

Abstract

The high content of free fatty acid (FFA) in crude palm oil has become a challenge in refining process due to refining losses and possible bleachability problems. Nowadays, alkaline and distillation approaches are widely used in industry to remove FFA but certain factors such as high energy consumption, environmental pollution and cost had limited the usage. Organic Solvent Nanofiltration (OSN) is being studied as an alternative due to its lower energy consumption, easy scale up, lower cost and the loss of nutrients is minimal. The objective of this research is to study the feasibility of OSN to remove FFA from palm oil based on the rejection and flux of FFA and triglyceride (TG). Two parameters which are type of solvent used and the feed concentration of FFA were studied. Based on the result, acetone shows high solubility and diffusivity towards OSN membrane leading to high selectivity of FFA and high rejection of TG compared to hexane. The rejection of FFA increases with the concentration of FFA.