Application of Plastic Optical Fiber in Photocatalysis

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Application of Plastic Optical Fiber in Photocatalysis

Heerok Jeong, Hyunku Joo**^†, Sang Eun Park*, Myung Seok Jeon**, Chungmoo Auh** and Il Moon

Department of Chemical Engineering,

*Department of Environmental Engineering, Yonsei University, Seoul 120-749, Korea

**Solar Energy Conversion Research Team, Korea Institute of Energy Research, Daejeon 305-343, Korea (Received 22 May 2001; accepted 19 July 2001)

º £

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Abstract−In this study, the use of plastic optical fiber(POF) was presented as a light guide in photocatalysis. To do so a sim- ple method to remove the clad of POF was established and the most effective parameters on photocatalysis were investigated when used in a form of bundled array. Photocatalytic degradation of trichloroethylene(C₂HCl₃, TCE) and ethanol in the gas- phase was also performed by using TiO₂-coated plastic optical fiber reactor. Among 13 solvents with different solubility parameters and working groups, acetone was used to remove clad layer chemically, resulting in that optimized time of POF in acetone was selected 3 min to remove the clad layer completely. The photocatalytic activities of TiO₂-coated optical fiber reac- tor system was dependent on the coating thickness, diameter and total clad-stripped surface area of POF. In ethanol degrada- tion, in-situ FTIR measurement resulted in complete mineralization into CO₂.

Key words: Plastic Optical Fiber(POF), Photocatalytic Degradation, Trichloroethylene, TiO₂

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†To whom correspondence should be addressed.

E-mail: hkjoo@kier.re.kr

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Fig. 1. Schematic diagram of bundled POF.

Fig. 2. Effect of solvation time on the diameter of POF(SEM left: after 30 sec, right: after 3 min).

Fig. 3. Comparison of reactivity for TCE degradation between QOF and POF[1.0µl TCE in 650 ml reactor, 5 wt% P25 sol, 320 nm cut- off filter, ca. 32 mW/cm² at 360 nm, 12 fibers(30 cm)].

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ditions used for Fig. 3 except coating time).

Fig. 5. Effect of POF diameter on reactivity(under the same conditions used for Fig. 3 except POF diameter).

Fig. 6. Effect of total surface area on reactivity(under the same condi- tions used for Fig. 3 except 3 time coating and preillumination).

Fig. 7. Result of ethanol degradation with POF system(under the same conditions used for Fig. 3).

Fig. 8. Measurement of CO₂ in ethanol degradation with in-situ FTIR reactor.

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