Fabrication of Polyamide 6 /Activated Carbon Composite Nano Fibers for the Removal of Organic Dyes from Wastewater

Abstract

Background:
Environmental pollution caused by the discharge of wastewater containing organic dyes into water bodies is a significant global problem that poses serious threats to human health. Organic dyes are hazardous due to their toxicity and carcinogenic potential, and failure to remove them leads to contamination of water resources.

Objectives:
This study aimed to investigate the application of polyamide 6/activated carbon (PA6/AC) composite nanofibers for the adsorption of malachite green (MG) and carmoisine (CA) dyes from wastewater.

Materials and Methods:
Electrospun PA6 and PA6/AC nanofibers were fabricated and characterized using field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), nitrogen adsorption/desorption, water contact angle measurements, and tensile testing. Adsorption experiments were conducted to evaluate the effects of initial dye concentration, solution pH, contact time, and temperature on dye removal efficiency. Kinetic and isotherm models were applied to analyze the adsorption process.

Results:
FESEM analysis showed bead-free nanofibers with average diameters of 120 nm (PA6) and 104 nm (PA6/AC). Water contact angle measurements indicated increased hydrophilicity in PA6/AC fibers. The nanofibers achieved up to 99% removal of CA at 10 mg/L, pH = 2, and 120 minutes, while maximum adsorption of MG occurred at 5 mg/L, pH = 12, and 120 minutes. Adsorption kinetics followed the pseudo-second-order model, and the Langmuir isotherm best described equilibrium data.

Conclusion:
PA6/AC nanofiber mats exhibit excellent potential for removing organic dyes such as MG and CA from wastewater. They represent a promising material for water purification, and future studies should evaluate their performance in treating real wastewater samples.