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Azo-Dye-Functionalized Polycarbonate Membranes for Textile Dye and Nitrate Ion Removal
Carrie Cockerham1, Ashton Caruthers2,3, Jeremy McCloud4,5
1Department of Civil Engineering, Marshall University, Huntington, WV 25755, USA.
Micromachines
|April 23, 2022
Summary
Functionalized polycarbonate membranes effectively remove azo dyes from wastewater, achieving 96.4% rejection. This novel filtration method offers a promising solution for textile industry wastewater treatment challenges.
Area of Science:
- Environmental Science
- Materials Science
- Chemical Engineering
Background:
- Textile industry wastewater poses challenges due to dye pollution.
- Traditional treatments struggle with dye retention and harmful byproduct formation.
- Azo dyes are common, persistent pollutants in industrial effluents.
Purpose of the Study:
- To develop and evaluate a novel filtration membrane for azo dye removal.
- To investigate the functionalization of polycarbonate membranes for enhanced dye capture.
- To assess the membrane's performance in removing specific azo dyes and inorganic ions.
Main Methods:
- Track-etched polycarbonate membranes (100-nm pores) were functionalized with Direct Red 80 azo dye.
- Dye rejection was measured using ultraviolet-visible spectroscopy.
- Ion rejection was assessed using ion-selective electrodes.
- Filtration experiments were conducted at controlled flow rates.
Main Results:
- Functionalized membranes achieved 96.4 ± 1.4% rejection of 50 µM Direct Red 80 at 114 ± 5 µL/min.
- Rejection of similar azo dyes increased from 26.3% to 53.2%.
- Moderate rejection of sodium nitrate ions (17.9%–31.1%) was observed at higher concentrations and flow rates.
Conclusions:
- Functionalized polycarbonate membranes show high efficacy in removing azo dyes from wastewater.
- The method offers a stable and efficient approach to textile dye wastewater treatment.
- Further research can optimize membrane functionalization for broader pollutant removal.
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