Photocatalytic degradation of polyethylene glycol using visible-light driven photocatalysts

• Main Authors: Yu-Chen Wang, 王彧宸
• Other Authors: Ｗen-Churng Lin
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/83798161293376793629

碩士 === 崑山科技大學 === 環境工程研究所 === 102 === Large amounts of synthetic polymer are used for various industrial and/or general applications. A significant proportion appears in the form of waste and is discarded into the environment. Most of them are recalcitrant to biodegradation and conventional chemical oxidation using oxidants. In this project, the decomposition of various PEG (e.g., PEG 2000, PEG 4000, PEG 6000, and PEG 20000) by means of visible-light photocatalytic degradation has been studied. 　　Photocatalytic nanocrystalline neat TiO2 powders were prepared from alkoxide solutions via the sol-gel method. The alkoxide solutions were formed by adding titanium isopropoxide and acetylacetone (as a chelating reagent) to isopropanol. The surface of anatase TiO2 nanoparticles could be modified by ferric acetylacetonate complex Fe(acac)3. This modification could improve the dispersion of TiO2 in polymer and also the photocatalytic activity. The photodegradation of PEG (PEG 2000, PEG 4000, and PEG 6000) catalyzed by modified TiO2 were extensively studied in comparison with that by neat TiO2. 　　Antimony trisulfide (Sb2S3) nanorods can be employed as photocatalyst with visible-light activity. In this work, different crystal form antimony trisulfide nanorods were synthesized using the refluxing method. The phase, morphologies, compositions and optical properties of the as-prepared Sb2S3 nanorods have been carried out by X-ray diffraction, X-ray photoelectron spectroscopy, nitrogen adsorption (Brunauer–Emmett–Teller -specific surface area), scanning electron microscopy, transmission electron microscopy, and Ultraviolet-Visible spectroscopy. The photodegradation of PEG (PEG 20000) catalyzed by visible-light driven Sb2S3 photocatalysts were extensively studied. During the degradation, we could observe that the polymer lost its weight gradually, the molecular weight of the polymer decreased, and the molecular weight distribution index increased. The results accorded with the degradation characters have been discussed in detail.