Selective Green Colorimetric Liquid- and Solid-Based Determination of Furfural in Power Transformer Insulating Fluid

Area of Science:

• Analytical Chemistry
• Green Chemistry

Background:

• Furfural (FF) indicates Maillard reactions in food and degradation in transformer insulation.
• Conventional methods for furfural detection can be toxic and complex.

Purpose of the Study:

• To develop a novel, green, and sensitive colorimetric assay for furfural quantification.
• To enable on-site analysis of furfural in power transformer insulating fluid.

Main Methods:

• Developed a Stenhouse reaction-based colorimetric chemosensory assay using furfural-bis-(4-aminophenyl) disulfide (APDS).
• Utilized UV-vis spectroscopy and colorimetric analysis for furfural quantification.
• Formulated an APDS strip with polyethylene glycol for solid-phase analysis.

Main Results:

• The assay demonstrated high sensitivity (0.00024 mM furfural) and selectivity for furfural.
• A visible color change was observed at 0.005 mM furfural, detectable by the naked eye.
• The method was successfully applied to quantify furfural in power transformer insulating fluid (0-1 ppm).

Conclusions:

• The developed APDS assay is a novel, green, and sensitive method for furfural detection.
• The assay offers a simpler, safer alternative to conventional methods, enabling on-site analysis.
• Successful surface Stenhouse coupling was confirmed by X-ray photoelectron spectroscopy.