Computer Aided Molecular Design for alternative sustainable solvent to extract oil from palm pressed fibre

Abstract

Palm pressed fibre (PPF) is one of the by-products from palm oil milling process which is conventionally burned as fuel to produce energy to support the milling operation. PPF typically contains 5–6% of residual palm oil, which can be further recovered as by-product before using it as fuel in boiler. Therefore, it has propagated great interest in developing technologies to extract the residual oil from PPF. Based on the currently available technologies, hexane cold extraction is the most established method for recovering the residual oil. However, the extracted residual oil via hexane is not suitable for food applications due to the toxicity of hexane. Besides, the low recovery of carotene from the residual oil is another major concern of using hexane as solvent in the cold extraction. Therefore, there is a need to identify an alternative solvent to recover the residual oil from PPF. In this work, Computer Aided Molecular Design (CAMD) technique is adapted to identify alternative solvents which possess the most desirable attributes for this application. This application of CAMD is unique because it is important to optimize the physical properties of the potential solvent along with safety and health attributes in order to use in food industries. Moreover, the safety and health indexes depend on the physical properties of the final solvent and the abrupt changes of these indexes must be tracked simultaneously with the changes in properties. The proposed approach can identify alternative solvents that extract residual oil from PPF with the highest retention of carotene. To trade off the optimisation objective of the recovery of carotene and total health and safety impacts, fuzzy optimisation based approach for solvent design has been developed.