Novel TiO2 Nanoparticles/Polysulfone Composite Hollow Microspheres for Photocatalytic Degradation.

Shangying Zhang,Youhai Yu,Guangtao Qian,Chunhai Chen,Fengna Dai,Qi Wang,Yangyang Gu

doi:10.3390/polym13030336

Abstract

Nanosized titanium oxide (TiO2) material is a promising photocatalyst for the degradation of organic pollutants, whereas the difficulty of its recycling hinders its practical application. Herein, we reported the preparation of a novel titanium oxide/polysulfone (TiNPs/PSF) composite hollow microspheres by the combination of Pickering emulsification and the solvent evaporation technique and their application for the photodegradation of methyl blue (MB). P25 TiO2 nanoparticles dispersed on the surface of PSF microspheres. The porosity, density and photoactivity of the TiNPs/PSF composite microsphere are influenced by the TiO2 loading amount. The composite microsphere showed good methyl blue (MB) removal ability. Compared with TiO2 P25, and PSF, a much higher MB adsorption speed was observed for TiNPs/PSF microspheres benefited from their porous structure and the electrostatic attractions between the MB+ and the negatively charged PSF materials, and showed good degradation efficiency. For TiNPs/PSF composite microsphere with density close to 1, a 100% MB removal (10 mg L−1) within 120 min at a catalyst loading of 2.5 g L−1 can be obtained under both stirring and static condition, due to well dispersing of TiO2 particles on the microsphere surface and its stable suspending in water. For the non-suspended TiNPs/PSF composite microsphere with density bigger than 1, the 100% MB removal can be only obtained under stirring condition. The removal efficiency of MB for the composite microspheres retained 96.5%, even after 20 cycles. Moreover, this composite microsphere also showed high MB removal ability at acidic condition. The high catalysis efficiency, excellent reusability and good stability make this kind of TiNPs/PSF composite microsphere a promising photocatalyst for the water organic pollution treatment.

Highlights

With the rapid development of urbanization and industry, the problems of water pollution have been concerned
The adsorption and photodegradation of methyl blue (MB) were studied under static condition
The lower efficiency under non-stirring state is attributed to a part of catalyst particles settled at the bottom of the reactor, which decrease the utilization rate of catalyst, and the result is coherent with reported in the literature [41]

Summary

Introduction

With the rapid development of urbanization and industry, the problems of water pollution have been concerned. Magallanes et al prepared floating photocatalysts based on composites of low-density polyethylene (LDPE) and TiO2 P25, which showed show higher activity for degradation of methylene blue than pure TiO2 P25 under special constraining conditions, i.e., no stirring and no oxygenation. They believed that the higher activity for floating catalyst is related the more efficient illumination and more efficient oxygenation on the water surface [22]. Reports on PSF/TiO2 composite photocatalysts are limited to membrane materials [24] In this contribution, we report the preparation and use of a kind of TiO2 nanoparticle (TiNPs)/PSF substrate hollow microsphere composite (donated as TiNPs/PSF) as mobile photocatalysts for wastewater treatment for the first time. The influence of TiO2 loading amount on the morphologies, properties and photoactivities of the TiNPs/PSF composite microspheres on methyl blue (MB) were studied in detail

Materials

Results and Discussion

Scanning

Results

Conclusions