Photocatalytic Degradation of Methylene blue and Acetaldehyde by Tio2/Glaze Coated Porous Red Clay Tile

다국어 초록 (Multilingual Abstract)

Nanosized TiO2 sol synthesized by sol-gel method was successfully coated on the porous red clay tile (PRC tile) with micrometer sized pores. PRC tile was first coated with a low- firing glaze (Glaze coated PRC tile) and then TiO2 sol was coated on the glaze layer. The low-firing glaze was blended at various blending ratios with frit and feldspar, a blending ratio which is glazed at 700 ℃ was selected as an optimum condition. Then TiO2 sol synthesized from TTIP was dip coated on the glazed layer (TiO2 /glaze coated PRC tile), and it was calcined again at 500 ℃. Here, these calcination temperatures were selected to induce a strong bonding by sintering between TiO2 layer and glaze layer and to prevent the nanosized TiO2 sol particles from swamping into the glaze layer. Photocatalytic activity on the TiO2 /glaze coated PRC tile was evaluated by the extent of photocatalytic degradation of methylene blue and acetaldehyde. Methylene blue with the high concentration of 150 ㎎/ℓ on the surface of TiO2 /glaze coated PRC tile was almost photodegradated within 5 hours under the condition of average UV intensity of 0.275 ㎽/㎝2, while no photodegradation reaction of methylene blue occurred on the glaze coated PRC tile without TiO2 . Another photocatalytic activity was also evaluated by measuring the extent of photocatalytic degradation of gaseous acetaldehyde. The photodegradation efficiency in TiO2 /glaze coated PRC tile showed about 77 % photocatalytic degradation of acetaldehyde from 45,480 ㎎/ℓ to 10,536 ㎎/ℓ after the UV irradiation of 14 hours, but only about 16 % in the case of the glaze coated PRC tile.

다국어 초록 (Multilingual Abstract)

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