Essential Oil Extraction for All: A Flexible and Modular System for Citrus Biomass Waste

The essential oil industry is a growing sector that generates 5.41 billion USD annually worldwide. Essential oils are widely used in medicine, agriculture, and perfumery. Although there are available systems in the market for domestic essential oil extraction, replacing the entire equipment in case of repair or malfunction can be costly. To address this problem, a pilot-scale essential oil extractor system was developed that operates through hydrodistillation. This system was used to process various citrus wastes such as green and yellow lemons, oranges, grapefruits, and Eucalyptus globulus. A factorial design was performed, and the best conditions were used to extract other biomass residues. GC-MS analysis revealed that the primary compound for orange, grapefruit, and green lemon essential oils is D-imonene, with 95.4%, 95.5%, and 49.2%, respectively. For yellow lemon the primary compound appeared to be Dlimonene with 73.0% content, though the GC/MS data were less clear, and for eucalyptus, it is eucalyptol with 71.0%. The estimated production costs were 0.01 USD/mL, 0.04 USD/mL, 0.06 USD/mL, 0.07 USD/mL, and 0.15 USD/mL for orange, grapefruit, green lemon, yellow lemon, and eucalyptus essential oils, respectively. Therefore, the developed system is a competitive option for pilot-scale essential oil extraction.

Automated summary

The global essential oil industry generates annual revenue of 5.41 billion USD and is widely used in medicine, agriculture, and perfumery. To address the high cost of equipment repair and malfunction, a pilot-scale essential oil extractor system operating through hydrodistillation was developed. This system successfully processed various citrus wastes and revealed the primary compounds present in different essential oils through GC-MS analysis. The estimated production costs for different essential oils were also determined.