Biodiesel is becoming an increasingly important alternative fuel, driven by its renewable origin and its potential to reduce environmental impact compared to conventional fossil fuels. As its adoption grows, so does the need for reliable analytical techniques capable of ensuring fuel quality and regulatory compliance.
Among the key parameters that must be monitored in biodiesel characterization, FAME (Fatty Acid Methyl Esters) content plays a central role, directly influencing fuel performance, oxidation stability, and compliance with international standards alongside other critical parameters such as cetane number and corrosion potential.
FT-IR spectroscopy is one of the most effective techniques for FAME quantification, offering speed, reliability, and minimal sample preparation. . The method exploits a fundamental spectral property: the ester bonds in biodiesel (FAME) absorb infrared light at a specific wavelength — approximately 1745 cm⁻¹ — while fossil diesel is essentially transparent at that same point. This selectivity makes FT-IR a highly specific and direct tool for FAME determination in blended fuels.
While both standards rely on FT-IR analysis, they differ in workflow and sample handling. EN 14078 requires dilution in hexane with calibration based on carbonyl peak intensity, and is recognized for its high precision, representing the reference standard for both European and global markets. ASTM D7371, on the other hand, enables direct analysis without sample dilution through ATR-based measurement, offering a faster workflow suited to high-throughput environments. Supporting both approaches provides laboratories with significant flexibility across different operational and regulatory contexts.
To improve analytical efficiency and repeatability, REDshift developed LAS, the Liquid Handling Autosampler, an automated solution designed for FT-IR and ATR liquid analysis workflows. The system automates sample handling directly from closed vials while integrating washing and drying routines to minimize carry-over and contamination between analyses.
The LAS platform supports up to 30 vial positions and can handle volatile solvents and high-viscosity samples up to ISO VG 1000.
One of the main advantages of the REDshift LAS system is its ability to improve analytical repeatability while reducing manual intervention. Automated purging and drying routines help mitigate interference effects caused by residual water vapor in the carbonyl spectral region, contributing to more reliable FAME quantification results. In biodiesel applications, the system demonstrated excellent analytical linearity, supporting highly accurate concentration measurements.
The LAS accessory is compatible with both transmission IR cells and ATR cells, allowing laboratories to select the most appropriate analytical configuration based on sensitivity requirements, workflow preferences, and regulatory standards.
Beyond biodiesel analysis, the REDshift LAS platform can also support applications involving lubricants, pharmaceutical products, environmental samples, and food & beverage analysis, making it a versatile automation solution for modern FT-IR laboratories.
