Study On Photocatalysis Of Air-Cleaning Coating And The Aging Performance Of Coated Papeb

Because of the advantages and disadvantages of nano-titanium dioxide(TiO2) in photocatalysis and (3-cyclodextrin in inclusion, it’s a feasible to combine β-CD with nano-TiO2to control indoor organic pollutants. In this paper, the preparation of nano-TiO2, coating and coated paper and the photocatalytic purification performance and aging performance of TiO2/β-CD coated paper were studied in detail.The anatase TiO2nano-power was prepared by the sol-gel method. The size, appearance, structure and property of TiO2were analyzed with XRD. SEM, FT-IR and AFM. The results showed that the samples were anatase TiO2particles with average size of20nm in diameter. The photocatalytic oxidation properties were examined by the degradation of methyl red. When the concentration of methyl red was20mg/L and the dosage of the powders was0.7g/L, the removal rate of methyl red was about95.58%after irradiated half hour with the8W ultraviolet lamp with wavelength of365nm.The photocatalytic degradation of xylene and formaldehyde by the nano-TiO2and nano-TiO2/β-CD coated papers in the self-designed air-tight devices and the aging properties of the coated papers were studied. The results showed that both coated papers had activities in photocatalytic degradation of xylene and formaldehyde. Paper coated with nano-TiO2/β-CD had a better effect on degradation than the paper coated with nano-TiO2only, and β-CD and nano-TiO2have significant synergistic effect on the degradation of xylene and formaldehyde. For the nano-TiO2/β-CD coated paper, the degradation efficiency of xylene at the concentration of292mg/m3was up to78%after2weeks under the radialization of indoor light, and the degradation of formaldehyde at the concentration of274mg/m3was up to98.57%. However, the irradiating both by the UV light and natural light indoor had negative impact on physical properties of papers.The color reversion experiment of different ratios of nano-TiO2/β-CD coated papers in a standard NCE (Network of Centres of Excellence) photoreactor were studied. Both the structure of the coated paper and components of the coating also were analysed with SEM and FT-IR.The results showed that the components of the coating did not change except for a little agglomeration on the surface of the coating after irradiated30hours. The physical properties of the paper coated with nano-TiO2/β-CD coated paper were superior to base paper, and both the physical properties and light properties of coated paper adding2%nano-TiO2and1%β-CD was the best, while3%nano-TiO2and1%β-CD accelerated the color reversion of the coated paper.