Techno-Economic-Environmental Analysis of Sustainable Anionic Biosurfactant Production from Palm Fatty Acid Distillate

Currently, there is increased interest in biosurfactants as a substitute for surfactants synthesized from petroleum due to their superior properties and biodegradability. Palm oil derivatives, which can be converted to various products, were selected for biosurfactant synthesis. This paper simulated the biosurfactant production process from palm fatty acid distillate, that is, methyl ester sulfonate (MES), alkyl sulfate, alkyl phosphate, and alkyl carboxylate. Aspen Plus software was used to estimate the thermodynamic properties of intermediate aliphatic organic acids, e.g., methyl ester sulfonic acid, fatty alcohol sulfuric acid, and fatty alcohol phosphoric acid. The chemical process equipment was designed and evaluated to be used in techno-economic analysis, with comparison to petroleum source surfactant production, that is, sodium dodecylbenzenesulfonate (SDBS). The total production cost of each biosurfactant was expressed in terms of minimum selling price. The profitability of each project was determined and compared using three economic indicators: net present value (NPV), payback period, and internal rate of return (IRR). The life cycle assessment methodology was then used to evaluate the environmental impact of surfactant production. The results showed that all surfactant production processes, except for alkyl phosphate, were attractive alternatives as the project yielded a positive value of NPV. The highest NPV of 13.1 million USD was obtained from the MES production process, while the maximum IRR of 79.81% and payback period of 1.49 years were obtained from the alkyl carboxylate production process at a capacity of 1 ton/h. However, the sulfate production process caused more environmental impact than the other two surfactants (MES and carboxylate) due to more CO2 emission per product unit at the level of 2.88 tons CO2/ton surfactant, which is also more than the SDBS surfactant production process that released 2.46 tons CO2/ton surfactant.