Development of a Novel Biocatalytic Process for the Synthesis of a New Biolubricant Derived from 1,10-Decanediol Based on Sustainability and Economic Efficiency

Branched esters are compounds with many applications in the chemical industry, ranging from the manufacture of biolubricants to the cosmetics industry. The traditionally chemical route results in low sustainable process and biocatalytic synthesis emerges as a sustainable alternative to produce these esters. The advantages offered by biotransformation are reaction specificity, enzymes biodegradability, mild reaction conditions and solvent-free systems. This avoids secondary reactions, reduces solvents waste generation and eliminates downstream separation steps. Therefore, high-purity products are obtained in a more profitable and sustainable way which conforms to ten of the twelve principles of green chemistry. In this research, we have successfully optimized the first-ever production of decane-1,10-diyl bis(2-methylhexanoate) (DDBMH) in a solvent-free reaction medium, utilizing the commercial biocatalyst Novozym® 435. Optimal conditions for synthesis have been determined (70 °C and biocatalyst concentration of 2.5% (w/w)) by testing 60–80 °C and 1.25–3.75% (w) ranges. The possible industrial implementation of the process requires an economic analysis which has examined the impact of various costs. The sustainability of the process has also been analyzed by determining different green metrics. Finally, the determination of the viscosity index (VI = 196.29) has allowed us to verify that the ester obtained can be used as a biolubricant.