Processes And Systems For Catalytic Manufacture Of Wax Ester Derivatives

What is this patent about?

’122 is related to the field of processing wax esters, specifically jojoba wax esters, for use in cosmetic and personal care products. Traditional methods of transesterification, which alter the physical properties of wax esters, often rely on chemical catalysts. These chemical processes can degrade desirable components naturally present in wax ester feedstocks, such as antioxidants and volatile compounds, and introduce undesirable byproducts.

The underlying idea behind ’122 is to use enzymatic catalysis with a lipase to transesterify wax esters, particularly jojoba wax esters. This enzymatic approach avoids the harsh conditions and side reactions associated with chemical catalysts. By using a lipase, the process can be performed at lower temperatures and ambient pressure, preserving the beneficial components of the feedstock and minimizing the formation of unwanted byproducts like methyl esters and free fatty alcohols.

The claims of ’122 focus on a continuous process for producing a jojoba wax ester product. The process involves continuously contacting a feedstock containing jojoba wax esters and hydrogenated jojoba wax esters with an immobilized lipase enzyme catalyst. The lipase then catalytically transesterifies the wax esters, resulting in a product containing transesterified wax esters and, importantly, retaining the feedstock's tocopherol (a natural antioxidant).

In practice, the feedstock is passed through a reactor containing the immobilized lipase. The continuous nature of the process allows for efficient and scalable production. The use of an immobilized lipase facilitates its reuse and prevents contamination of the product. The reaction conditions are mild enough to preserve heat-sensitive components like tocopherols, which contribute to the oxidative stability of the final product. The degree of hydrogenation of the jojoba wax esters can be controlled to tailor the dropping point of the final product.

Unlike chemical transesterification, the enzymatic process does not generate fatty acid methyl esters or free fatty alcohols. Furthermore, the enzymatic process surprisingly increases the oxidative stability index (OSI) of the transesterified product compared to the feedstock, indicating enhanced shelf life. The lipase catalyst also exhibits a longer lifespan than expected based on its use in triglyceride processing, achieving a higher product-to-catalyst ratio. This makes the enzymatic process more efficient and cost-effective.