Structural analysis and dye removal behavior of amorphous titania embedded poly(vinyl butyral) hybrid fiber

This study reports on the efficient methylene blue (MB) dye removal properties of a polyvinyl butyral (PVB)-amorphous titania (amTiO₂) hybrid fiber (PVB-amTiO₂F) made by air-gap spinning in acetone solvent. The successful fabrication of PVB-amTiO₂F was confirmed by employing Fourier transform infrared, scanning electron microscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, and energy dispersive X-ray measurement. Batch experiments were used to examine the cationic MB dye adsorption performance in the dark. The observed data showed that the developed PVB-amTiO₂F exhibited moderate adsorption efficiency (68-70%) which is comparable to other amorphous titania-rich adsorbents. The adsorption kinetics was well fitted with a pseudo-second-order model, suggesting that adsorption is mainly led by chemisorption. In addition, the MB degradation properties under visible light were also studied afterwards. A possible adsorption mechanism is discussed. Moreover, the as-fabricated fiber exhibited average to good reusability after 6 cycles. Only cationic MB dye solution was able to demonstrate such properties.