TiO2 Nanoparticle-Loaded Poly(NIPA-co-NMA) Fiber Web for the Adsorption and Photocatalytic Degradation of 4-Isopropylphenol.

Hideaki Tokuyama,Ryosuke Hamaguchi

doi:10.3390/gels8020137

Hideaki Tokuyama, Ryosuke Hamaguchi

Open Access

https://doi.org/10.3390/gels8020137

Copy DOI

Abstract

A TiO2 nanoparticle-loaded polymer fiber web was developed as a functional material with the ability to adsorb and photo-catalytically degrade organic pollutants in aquatic media. A linear copolymer of N-isopropylacrylamide (primary component) and N-methylol acrylamide (poly(NIPA-co-NMA)) was prepared, and composite fibers were fabricated by electrospinning a methanol suspension containing the copolymer and commercially available TiO2 nanoparticles. The crosslinking of the polymer via the formation of methylene bridges between NMA units was accomplished by heating, and the fiber morphology was analyzed by electron microscopy. 4-Isopropylphenol generated by the degradation of bisphenol A—one of the endocrine-disrupting chemicals—was used as the model organic pollutant. As poly(NIPA) is a thermosensitive polymer that undergoes hydrophilic/hydrophobic transition in water, the temperature-dependence of the adsorption and photocatalytic degradation of 4-isopropylphenol was investigated. The degradation rate was analyzed using a pseudo-first-order kinetic model to obtain the apparent reaction rate constant, kapp. The enhancement of the photocatalytic degradation rate owing to the adsorption of 4-isopropylphenol onto thermosensitive poly(NIPA)-based fibers is discussed in terms of the ratio of the kapp of the composite fiber to that of unsupported TiO2 nanoparticles. Based on the results, an eco-friendly wastewater treatment process involving periodically alternated adsorption and photocatalytic degradation is proposed.

Highlights

The removal of hazardous organic pollutants from water bodies and industrial waste streams has attracted considerable attention
We investigated the reusability of the supported photocatalytic system, the TiO2 nanoparticle-loaded fiber web in the degradation of 4-isopropylphenol at 50 ◦ C
Trospinning method method using using aa methanol methanol suspension suspension containing containing the thecopolymer copolymerand andcommercommertrospinning cially available TiO2 nanoparticles, and heated to crosslink the polymer via methylene cially available TiO2 nanoparticles, and heated to crosslink the polymer via methbridges derived from N-methylol acrylamide (NMA) units

Summary

Introduction

The removal of hazardous organic pollutants from water bodies and industrial waste streams has attracted considerable attention. BPA is converted to various intermediates such as 4-isopropylphenol, formic acid, and acetic acid, and to CO2 [2]

Methods

Results

Conclusion