Attachment of TiO2 Powders to Hollow Glass Microbeads: Activity of the TiO2‐Coated Beads in the Photoassisted Oxidation of Ethanol to Acetaldehyde.
Attachment of TiO2 Powders to Hollow Glass Microbeads: Activity of the TiO2‐Coated Beads in the Photoassisted Oxidation of Ethanol to Acetaldehyde.
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DOI：
10.1002/chin.199208027
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发表时间：
1992-02
期刊：
影响因子：
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通讯作者：
N. B. Jackson;C. Wang;Z. Luo;Jörg Schwitzgebel;J. Ekerdt;J. Brock;A. Heller
中科院分区：
文献类型：
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作者：
N. B. Jackson;C. Wang;Z. Luo;Jörg Schwitzgebel;J. Ekerdt;J. Brock;A. Heller
Methods for attaching n-TiQ particles to hollow microbeads of 80-100~ m average diam and 0.4-0.7 gcm-3 density are discussed. The floating photoactive microbeads were designed for use in solar-assisted oxidative dissolution of oil films on water. Photoactive beads caused the oxidation of ethanol molecules by dissolved dioxygen to acetaldehyde when exposed to> 3 eV incident photons. Particularly photoactive beads were obtained by attaching Degussa P25 TiO2 particles to aluminosilicate glass microbeads of-10~ m wall thickness by physisorbing the TiO2 particles and bonding thermally at 300~ The TiO2 thermally bonded to aluminosilicate beads was stable in water and UV light, producing 0.7 tool of acetaldehyde per einstein. Acetaldehyde was produced at an efficiency of 0.5 mol/e~ nstein in the photoassisted oxidation of ethanol on TiO2-activated borosilicate microbeads, which were made by a process where triethoxysilane was used as binder and ethanol was eliminated in the reaction with surface OH groups. One week of exposure to water caused the borosilicate glass microbeads to dissolve. The aluminosilicate glass was, however, not water-soluble, and the bound TiO2 particles did not detach from the bead.With the objective of photoassisting the oxidative dissolution of oil spills, we have undertaken a study of attaching n-TiO2 particles to hollow glass microbeads having sufficiently low densities to float on oil or water. Already, n-TiO2 is well known to photoassist the oxidation of organic pollutants in water by dioxygen (1-14). The attachment of photocatalytic semiconductors to supports has been the subject of a series of studies (15-29). This paper discusses methods of attachment of TiO2 to sodium borosilicate and aluminosilicate glasses and the photoactivity of the resulting microbeads.
