Voltammetric determination of sulfur in biodiesel microemulsion using a silver solid amalgam electrode

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Environmental Science

Background:

• Sulfur in biodiesel negatively impacts engine performance and increases toxic emissions.
• Accurate monitoring of sulfur content is crucial for biofuel quality control and environmental protection.

Purpose of the Study:

• To develop a simple, rapid, and sensitive adsorptive stripping voltammetry (AdSV) method for determining sulfur in biodiesel.
• To optimize and validate the electrochemical method for biodiesel microemulsion samples.

Main Methods:

• Development of an AdSV method utilizing a silver solid amalgam electrode (AgSAE).
• Evaluation using linear sweep (LSAdSV), square wave (SWAdSV), and differential pulse (DPAdSV) techniques.
• Optimization of a ternary microemulsion system (biodiesel/propan-1-ol/buffer) for sample analysis.

Main Results:

• The optimized microemulsion consisted of 25% buffer, 5.0% biodiesel, and 70% propan-1-ol.
• The method achieved a detection limit of 10^-7 mol L^-1 for sulfur.
• Recovery values ranged from 80% to 116%, indicating good accuracy.

Conclusions:

• The developed AdSV method is a promising alternative for fast and sensitive sulfur determination in biodiesel microemulsions.
• The method confirmed that sulfur levels in tested biodiesel samples were below regulatory limits.
• This technique contributes to ensuring biodiesel quality and mitigating environmental pollution.