Fragrance Applications

Fragrances are volatile organics derived from natural oils, such as citrus oils using adsorbent resins, or synthetic via catalysis/biocatalysis routes. While most scents and fragrances are purified via distillation, due to their high volatility, some will require resin purification when the fragrance volatility is close to its impurities. When distillation does not give you the selectivity you need, the various ion exchange resin chemistries available from Purolite will help.

While some fragrances and scents are part of the formulation of perfumes and colognes, some are added into cleaning detergents and home sprays such as linalool, which derives a pine smell that can be purified from its closest related impurity, gerol, via adsorption. Linalool can also be extracted out from coriander via the use of Purolite adsorption.

Pesticide Reduction in Citrus Essential Oils
Citrus oils are produced from fruit peels. Made mainly from low polar terpenes, they are prone to retain pesticides that have been used to protect fruits from illnesses during their ripening.

Pesticides are generally non-polar or very low-polar molecules; citrus oils are recovered from their emulsion in water through centrifugation and water does not dissolve all the molecules that remain in the oil, sometimes exceeding regulation limits. 

Moreover, the law sets limits for each pesticide, but sometimes in products from conventional agriculture, the total concentration of pesticides exceeds limits for commercial acceptance creating health and commercial problems. In the end, it is extremely difficult to manufacture citrus oils free from pesticides, even if fruits are grown in organic mode.

Specific ion-exchange resins manufactured by Purolite are able to eliminate or, at least, substantially reduce up to 90% pesticide content in citrus essential oils.

The system is based on an adsorption and ion exchange process in a column; citrus oils are percolated through cartridges loaded with specific ion exchangers. Through this system, it is possible to obtain an oil with greatly reduced pesticide content and with no significant change of other characteristics. Purolite can provide further information about operating conditions and expected results.

The resin system has been validated with very good results both with lemon oil and orange oil. Among common pollutants, just chlorpyrifos content remains unchanged, but considering that this pesticide has been recently banned in the European Union, it is a problem that will likely be resolved over time.