Techno-economic strategies for improving economic viability of β-carotene extraction using natural oil and supercritical solvent: A comparative assessment

• Published in: Algal research (Amsterdam) 2022-11, Vol.68, p.102875, Article 102875
• Main Authors: Chalermthai, Bushra, Giwa, Adewale, Moheimani, Navid, Taher, Hanifa
• Format: Article
• Language: English
• Subjects: Corn oil; Food-grade; Green solvents; Microalgae; Supercritical CO2; β-Carotene
• ISSN: 2211-9264; 2211-9264
• DOI: 10.1016/j.algal.2022.102875

Dunaliella salina microalgae is a third-generation feedstock that is both thermophilic and halophilic and can be used to produce nutritious food supplements such as β-carotene. Although several techno-economic studies have been carried out to produce the pigment, most of them considered traditional synthetic chemicals such as hexane, acetone, and petroleum ether as solvents for extracting β-carotene from D. salina. In this study, techno-economic assessment is carried out with the aim of producing food-grade products for human consumption via greener methods of D. salina cultivation, harvesting, and extraction. The techno-economic assessment of the extraction of β-carotene and by-products using natural and edible corn oil and supercritical CO2 reveal that the processes are economically feasible, with a payback time of 5.9 y and 2.7 y (for corn oil and SC-CO2 methods), respectively. The ROIs for both methods are also positive, that is, 16.9 % and 37.1 %, respectively and greater than the prevailing interest rates in most countries. Sensitivity analyses show that the payback time is most sensitive to the yield of β-carotene, its production output, and its selling price. This assessment shows that food-grade β-carotene can be produced in bulk quantity from D. salina (as an alternative to other sources such as carrots, tomatoes, pumpkins, etc.) in order to satisfy the growing demands of nutritional markets. •Food-grade β-carotene from corn oil and SC-CO2 can compete economically with existing methods.•Corn oil and SC-CO2 methods are both profitable, with payback times of 5.9 and 2.7 years, respectively.•The ROIs for both methods surpass the interest rate, that is, 16.9 % and 37.1 %, respectively.•SC-CO2 method is preferred over natural oil method due to process economics and environmental benefits.•Payback time is sensitive to selling price, yield, and production output of β-carotene.