Three-component deep eutectic solvent-based microextraction approach for biodiesel quality control: Determination of...

Area of Science:

• Analytical Chemistry
• Green Chemistry
• Materials Science

Background:

• Biodiesel quality is crucial for performance and preventing corrosion.
• Water and metal catalysts/feedstock elements can degrade biodiesel.
• Existing analytical methods can be hazardous or complex.

Purpose of the Study:

• To develop a simple, environmentally friendly method for determining water and metals in biodiesel.
• To utilize a novel deep eutectic solvent for microextraction and analysis.
• To provide a safer alternative to Karl Fischer reagents and microwave mineralization.

Main Methods:

• Microextraction of water and metals from biodiesel into a choline chloride-lactic acid-cobalt chloride deep eutectic solvent.
• Colorimetric determination of water via color change (blue to pink).
• X-ray fluorescence spectrometry for metal analysis on impregnated filter paper.

Main Results:

• Detection limits of 100 mg kg⁻¹ for water and 0.03–3 mg kg⁻¹ for metals.
• Successful multicomponent analysis without hazardous reagents or sample pretreatment.
• Enrichment factors of 290–330 and relative standard deviation <15%.

Conclusions:

• The developed deep eutectic solvent-based method is effective for biodiesel quality control.
• This approach offers a safe, simple, and green alternative for analyzing key biodiesel contaminants.
• The technique facilitates accurate determination of water and diverse metal elements.