Solvent Vegetable oils are widely used in food, chemical, pharmaceutical, and cosmetic industries. They are obtained from various plant sources, such as soybean, rapeseed, peanut, corn, olive, etc. The extraction of vegetable oils is a crucial step in the production process, as it affects the yield, quality, and cost of the final products. There are different methods for extracting vegetable oils, such as mechanical pressing, solvent extraction, supercritical fluid extraction, etc. Among them, solvent extraction is the most common and efficient one, as it can extract more oil from the plant materials, especially those with low oil content or high oil viscosity. However, solvent extraction also poses some challenges, such as the choice of the solvent, the recovery of the solvent, the environmental impact of the solvent, etc. Hexane is a straight-chain alkane with six carbon atoms and the molecular formula C6H14. It is a colorless, odorless, and highly volatile liquid, with a boiling point of about 69 °C. It is widely used as a cheap, relatively safe, largely unreactive, and easily evaporated non-polar solvent. Hexane is also the most commonly used solvent for vegetable oil extraction, as it has a high affinity for oil and a low affinity for water. Hexane can dissolve up to 70% of oil from the plant materials, leaving behind a solid residue called oil cake, which can be used as animal feed or fertilizer. However, hexane is not a pure substance, but a mixture of different isomers and impurities, such as pentane, heptane, benzene, sulfur, lead, arsenic, etc. These impurities can affect the quality and safety of the extracted oil, as well as the health and environment of the workers and consumers. Therefore, the purity and composition of hexane are important factors to consider when choosing a solvent for vegetable oil extraction. n-Hexane is the most stable and abundant isomer of hexane, with a boiling point of about 68 °C. It is a refined grade of hexane, which contains at least 60% of n-hexane and less than 40% of other isomers and impurities. n-Hexane has many advantages over other grades of hexane, such as: – Lower solvent loss: n-Hexane has a narrower distillation range (2-4 °C) than other grades of hexane (15 °C or more), which means it has less light and heavy fractions that can easily evaporate or remain in the oil cake. Therefore, n-Hexane can reduce the solvent loss per ton of oil extracted, which can save cost and energy. – Higher extraction capacity: n-Hexane is the most effective solvent for oil extraction, as it has the highest solubility and the lowest viscosity among the hexane isomers. Therefore, n-Hexane can extract more oil from the plant materials, especially those with high oil content or low oil viscosity, such as rapeseed, sunflower, etc. – Lower toxicity: n-Hexane has a lower content of benzene, sulfur, lead, arsenic, and other harmful impurities than other grades of hexane. These impurities can cause acute or chronic poisoning, cancer, or neurological damage to the workers and consumers who are exposed to them. Therefore, n-Hexane can reduce the health risks and the regulatory requirements associated with the solvent extraction process. – Lower corrosion: n-Hexane has a lower content of sulfur and other corrosive impurities than other grades of hexane. These impurities can react with the metal equipment and cause rust, wear, or leakage. Therefore, n-Hexane can extend the service life and the maintenance cycle of the extraction equipment, which can save cost and time. – Lower environmental impact: n-Hexane has a lower content of volatile organic compounds (VOCs) and other pollutants than other grades of hexane. These pollutants can cause air pollution, greenhouse effect, ozone depletion, or acid rain when they are released into the atmosphere. Therefore, n-Hexane can reduce the environmental impact and the emission control measures required for the solvent extraction process. In conclusion, n-Hexane is a superior solvent for vegetable oil extraction, as it can offer many benefits, such as lower solvent loss, higher extraction capacity, lower toxicity, lower corrosion, and lower environmental impact. n-Hexane can improve the efficiency, quality, safety, and sustainability of the vegetable oil production process, and create more value for the producers and consumers.