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Document Type |
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Article In Conference |
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Document Title |
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Surface Coating TiO2 on Sepiolite Fibers and Application in Paper-making Waste Water Treatment thereof Surface Coating TiO2 on Sepiolite Fibers and Application in Paper-making Waste Water Treatment thereof |
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Subject |
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كيمياء |
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Document Language |
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English |
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Abstract |
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For the past decade, the photocatalytic degradation of organic pollutants and
water treatment at semiconductors has been studied extensively. Such reactions have
usually been carried out using suspensions of semiconductor particles in aqueous
solutions irradiated with band-gap light. But it is evident that in any waste water
treatment process filtration and resuspension of semiconductor powders should be
avoided if possible. The purpose of this paper was to describe a novel method of
preparing photocatalyst Fe-TiO2 supported on sepiolite fibers with sol-gel technique
and to discuss the feasibility application in photocatalytic degradation of
paper-making waste water with chemical oxygen depletion(CODcr)(Potassium
dichromate method) as evaluation criterion of catalytic activity. As-fabricated
catalysts consisted of TiO2 particles impregnated with iron and dispersed on the
sepiolite fiber surfaces. Meanwhile, nano-TiO2 and TiO2 doped iron were prepared by
means of sol-gel approach in order to contrast catalytic properties among different
catalysts. These catalysts were characterized by surface area and pore size distribution
measurement, scanning electron microscope(SEM), transmission electron
microscope(TEM), X-ray diffraction(XRD), Fourier transform Infrared spectrometer
(FT-IR) and Laser dynamic light scatter(LDLS) , etc. The effects of parameters such
as the amount of Ti/sepiolite fibers, air flow, initial pH, H2O2, Fe-doped,
concentration of waste water, etc. were studied in detail. The results of FT-IR
elucidated that no obvious change was found in sepiolite fibers framework, indicating
Fe-TiO2 was coated on the sepiolite fiber surfaces and not introduced into sepiolite
fiber inside. With respect to morphologies of sepiolite fiber surfaces, observation of
SEM shown that roughness increased, which was on account of TiO2 coating. The
data of XRD and selected area electron diffraction(SAED) indicated that (Fe-)TiO2
was of anatase type. TiO2 high resolution TEM(HRTEM) result indicated crystalline
lattice defects were responsible for high catalytic activity. Comparison of catalytic
properties among catalysts shown that the presence of sepiolite in the support
preparation and its role as a matrix over which TiO2 particles were distributed seems
to play an important effect in the migration process of oxygen species through the
support vacancies. On the basis of these properties, the most promising carriers to be
used in a paper-making waste water treatment were selected.
Keywords: sepiolite fibers; surface coating; photocatalyst; characterization |
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Conference Name |
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Tenth International Symposium on Heterogeneous Catalysis |
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Duration |
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From : 22/8/1429 AH - To : 26/8/1429 AH
From : 23/8/2008 AD - To : 27/8/2008 AD |
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Publishing Year |
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1429 AH
2008 AD |
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Article Type |
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Article |
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Added Date |
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Wednesday, February 18, 2009 |
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Researchers
| Guang-Jian Wang | Guang-Jian Wang | Researcher | Doctorate | |
| Yuran Wang | Yuran Wang | Researcher | Doctorate | |
| Guangqing2 Liu | Guangqing2 Liu | Researcher | Doctorate | |
| Zheng-Xing Yang | Zheng-Xing Yang | Researcher | Doctorate | |
| Shi-Fu Chen | Shi-Fu Chen | Researcher | Doctorate | |
| Ming-Xia Xu | Ming-Xia Xu | Researcher | Doctorate | |
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