Separation of Water in Diesel Using Filter Media Containing Kapok Fibers

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Traditional water-repellent filters struggle with surfactant-laden low sulfur diesel and ultra low sulfur diesel (ULSD).
• High surfactant content in diesel fuels reduces the effectiveness of conventional water separation media.

Purpose of the Study:

• To develop and evaluate a novel dual-layer filter medium for improved water separation from diesel fuel.
• To investigate the impact of varying kapok fiber content on filter performance.

Main Methods:

• Fabrication of a dual-layer filter medium using hydrophilic glass microfibers and hydrophobic fibers (kapok, bi-component PET).
• Testing separation efficiency across different kapok fiber concentrations (0-80 wt%) and varying water-in-diesel interfacial tension (IFT).
• Comparison with commercial polybutylene terephthalate (PBT) and cellulose fiber filter samples.

Main Results:

• A filter medium with 20 wt% kapok fibers in the upstream layer achieved 89.5% separation efficiency.
• This optimized filter demonstrated superior performance across a range of interfacial tensions (IFT) compared to commercial filters.
• Separation efficiency reached 99.5% at 21 mN/m IFT, significantly outperforming commercial alternatives.

Conclusions:

• The developed dual-layer filter medium offers enhanced water separation capabilities for diesel fuels.
• Kapok fiber content is a critical factor in optimizing the performance of these novel filters.
• The new filter design presents a viable solution for challenges posed by modern diesel fuel compositions.