청정기술 (Clean Technology)

  • 제18권4호
  • /
  • Pages.419-425
  • /
  • 2012
  • /
  • 1598-9712(pISSN)
  • /
  • 2288-0690(eISSN)
한국청정기술학회 (The Korean Society of Clean Technology)
권호 표지
DOI QR코드

DOI QR Code

Photocatalysis of Sub-ppm-level Isopropyl Alcohol by Plug-flow Reactor Coated with Nonmetal Elements Irradiated with Visible Light

  • Jo, Wan-Kuen (Department of Environmental Engineering, Kyungpook National University)
  • 투고 : 2012.10.24
  • 심사 : 2012.12.07
  • 발행 : 2012.12.31
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

본 연구는 황 원소와 질소 원소가 도핑된 이산화티타늄의 특성을 조사하고 8-와트(W) 일반 램프와 가시광선 영역의 발광 다이오드 조사 조건에서 낮은 농도수준의 가스상 이소프로필 알코올(isopropyl alcohol, IPA)의 광촉매적 분해능에 대하여 조사하였다. 또한, 이소프로필 알코올의 광촉매 분해시 발생되는 아세톤의 생성에 대해서도 조사하였다. 황 원소와 질소 원소가 도핑된 이산화티타늄의 표면 조사결과, 두 촉매들은 가시광선 조사(visible light-emitting-diodes, LEDs)에 의해 효율적으로 활성화될 수 있는 것으로 나타났다. 두 촉매 모두에 대하여, 공기 유량이 감소함에 따라 이소프로필 알코올의 제거 효율이 증가하는 것으로 나타났다. 황 도핑 촉매의 경우, 유량이 0.1 L $min^{-1}$일 때 이소프로필 알코올 제거효율이 거의 100%로 나타난 반면에 유량이 2.0 L $min^{-1}$일 때 이소프로필 알코올 제거효율은 39%로 나타났다. 질소 도핑 촉매의 경우에는, 유량이 0.1 L $min^{-1}$일 때 이소프로필 알코올 제거효율이 거의 100%로 나타난 반면에 유량이 2.0 L $min^{-1}$일 때 이소프로필 알코올 제거효율은 90% 이상으로 나타났다. 이소프로필 알코올 제거 효율과는 달리, 유량 감소에 따라 아세톤 생성율은 감소하는 것으로 나타났다. 결과적으로, 아세톤 생성을 최소화하고 이소프로필 알코올 제거 효율을 높이기 위해서는 질소 도핑 촉매를 낮은 유량 조건에서 작동시키는 것이 나은 것으로 나타났다. 또한, 이소프로필 알코올 제거를 위해 가시광선 조사 발광 다이오드보다 8-와트 일반램프가 효율적인 것으로 나타났다.

This work explored the characteristics and the photocatalytic activities of S element-doped $TiO_2$ (S-$TiO_2$) and N element-doped $TiO_2$ (N-$TiO_2$) for the decomposition of gas-phase isopropyl alcohol (IPA) at sub-ppm concentrations, using a plug-flow reactor irradiated by 8-W daylight lamp or visible light-emitting-diodes (LEDs). In addition, the generation yield of acetone during photocatalytic processes for IPA at sub-ppm levels was examined. The surface characteristics of prepared S- and N-$TiO_2$ photocatalysts were analyzed to indicate that they could be effectively activated by visible-light irradiation. Regarding both types of photocatalysts, the cleaning efficiency of IPA increased as the air flow rate (AFR) was decreased. The average cleaning efficiency determined via the S-$TiO_2$ system for the AFR of 2.0 L $min^{-1}$ was 39%, whereas it was close to 100% for the AFR of 0.1 L $min^{-1}$. Regarding the N-$TiO_2$ system, the average cleaning efficiency for the AFR of 2.0 L $min^{-1}$ was above 90%, whereas it was still close to 100% for the AFR of 0.1 L $min^{-1}$. In contrast to the cleaning efficiencies of IPA, both types of photocatalysts revealed a decreasing trend in the generation yields of acetone with decreasing the AFR. Consequently, the N-$TiO_2$ system was preferred for cleaning of sub-ppm IPA to S-$TiO_2$ system and should be operated under low AFR conditions to minimize the acetone generation. In addition, 8-W daylight lamp exhibited higher cleaning efficiency of IPA than for visible LEDs.

키워드

참고문헌

  1. Bouzaza, A., Vallet, C., and Laplanche, A., "Photocatalytic Degradation of Some VOCs in the Gas Phase Using an Annular Flow Reactor: Determination of the Contribution of Mass Transfer and Chemical Reaction Steps in the Photodegradation Process," J. Photochem. Photobiol. A, 177, 212-217 (2007).
  2. Sekiguchi, K., Morinaga, W., Sakamoto, K., Tamura, H., Yasui, F., Mehrjouei, M., Muller, S., and Möller, D., "Degradation of VOC Gases in Liquid Phase by Photocatalysis at the Bubble Interface," Appl. Catal., 97, 190-197 (2010). https://doi.org/10.1016/j.apcatb.2010.03.039
  3. Herrmann, J. M., "Fundamentals and Misconceptions in Photocatalysis," J. Photochem. Photobiol. A, 216, 85-93 (2010). https://doi.org/10.1016/j.jphotochem.2010.05.015
  4. Han, F., Kambala, V. S. R., Srinivasan, M., Rajarathnam, D., and Naidu, R., "Tailored Titanium Dioxide Photocatalysts for the Degradation of Organic Dyes in Wastewater Treatment: A Review," Appl. Catal. A, 359, 25-40 (2009). https://doi.org/10.1016/j.apcata.2009.02.043
  5. Paz, Y., "Application of $TiO_{2}$ Photocatalysis for Air Treatment: Patents' Overview," Appl. Catal. B, 99, 448-460 (2010). https://doi.org/10.1016/j.apcatb.2010.05.011
  6. Chatterjee, D., and Dasgupta, S., "Visible Light Induced Photocatalytic Degradation of Organic Pollutants," J. Photochem. Photobiol. C, 6, 186-205 (2005). https://doi.org/10.1016/j.jphotochemrev.2005.09.001
  7. Yamada, K., Yamane, H., Matsushima, S., Nakamura, H., Ohira, K., Kouya, M., and Kumada, K., "Effect of Thermal Treatment on Photocatalytic Activity of N-doped $TiO_{2}$ Particles under Visible Light," Thin Solid Films, 516, 7482-7487 (2008). https://doi.org/10.1016/j.tsf.2008.03.041
  8. Bayati, M. R., Moshfegh, A. Z., and Golestani-Fard, F., "On the Photocatalytic Activity of the Sulfur Doped Titania Nanoporous Films Derived via Micro-arc Oxidation," Appl. Catal. A, 389, 60-67 (2010). https://doi.org/10.1016/j.apcata.2010.09.003
  9. Jo, W. K., and Yang, C. H., "Visible-light-induced Photocatalysis of Low-level Methyl-tertiary Butyl Ether (MTBE) and Trichloroethylene (TCE) Using Element-doped Titanium Dioxide," Build. Environ., 45, 819-824 (2010). https://doi.org/10.1016/j.buildenv.2009.08.021
  10. Sun, H., Wang, S., Ang, H. M., Tade, M. O., and Li, Q., "Halogen Element Modified Titanium Dioxide for Visible Light Photocatalysis," Chem. Eng. J., 162, 437-447 (2010). https://doi.org/10.1016/j.cej.2010.05.069
  11. Mahdjoub, N., Allen, N., Kelly, P., and Vishnyakov, V., "SEM and Raman Study of Thermally Treated $TiO_{2}$ Anatase Nanopowders: Influence of Calcination on Photocatalytic Activity," J. Photochem. Photobiol. A, 211, 59-64 (2010). https://doi.org/10.1016/j.jphotochem.2010.02.002
  12. Luis, A. M., Neves, M. C., Mendonca, M. H., and Monteiro, O. C., "Influence of Calcination Parameters on the $TiO_{2}$ Photocatalytic Properties," Mater. Chem. Phys., 125, 20-25 (2011). https://doi.org/10.1016/j.matchemphys.2010.08.019
  13. http://en.wikipedia.org/wiki/Light-emitting_diode
  14. Jia, C., Batterman, S., and Godwin, C., "VOCs in Industrial, Urban and Suburban Neighborhoods-Part 2: Factors Affecting Indoor and Outdoor Concentrations," Atmos. Environ., 42, 2101-2116 (2008). https://doi.org/10.1016/j.atmosenv.2007.11.047
  15. Vildozo, D., Ferronato, C., Sleiman, M., and Chovelon, J. -M., "Photocatalytic Treatment of Indoor Air: Optimization of 2- propanol Removal Using a Response Surface Methodology (RSM)," Appl. Catal. B, 94, 303-310 (2010). https://doi.org/10.1016/j.apcatb.2009.11.020
  16. Jo, W. K., and Kim, J. T., "Application of Visible-light Photocatalysis with Nitrogen-doped or Unmodified Titanium Dioxide for Control of Indoor-level Volatile Organic Compounds," J. Hazard. Mater., 164, 360-366 (2009). https://doi.org/10.1016/j.jhazmat.2008.08.033
  17. Horikawa, T., Katoh, M., and Tomida, T., "Preparation and Characterization of Nitrogen-doped Mesoporous Titania with High Specific Surface Area," Microp. Mesop. Mater., 110, 397-404 (2008). https://doi.org/10.1016/j.micromeso.2007.06.048
  18. Qin, X., Jing, L., Tian, G., Qu, Y., and Feng, Y., "Enhanced Photocatalytic Activity for Degrading Rhodamine B Solution of Commercial Degussa P25 $TiO_{2}$ and its Mechanisms," J. Hazard. Mater., 172, 1168-1174 (2009). https://doi.org/10.1016/j.jhazmat.2009.07.120
  19. Nam, S. H., Kim, T. K., and Boo, J. H., "Physical Property and Photo-catalytic Activity of Sulfur Doped $TiO_{2}$ Catalysts Responding to Visible Light," Catal. Today, 185, 259-262 (2012). https://doi.org/10.1016/j.cattod.2011.07.033
  20. Ohno, T., Akiyoshi, M., Umebayashi, T., Asai, K., Mitsui, T., and Matsumura M, "Preparation of S-doped $TiO_{2}$ Photocatalysts and their Photocatalytic Activities under Visible Light," Appl. Catal. A, 265, 115-121 (2004). https://doi.org/10.1016/j.apcata.2004.01.007
  21. Soler-Illia, G. J. A. A., Louis, A., and Sanchez, C., "Sybthesis and Characterization of Mesostructured Titania-based Materials through Evaporation-induced Self-assembly," Chem. Mater., 14, 750-759 (2002). https://doi.org/10.1021/cm011217a
  22. Peng, T., Zhao, D., Dai, K., Shi, W., and Hirao, K., "Synthesis of Titanium Dioxide Nanoparticles with Mesoporous Anatase Wall and High Photocatalytic Activity," J. Phys. Chem. B, 109, 4947-4952 (2005). https://doi.org/10.1021/jp044771r
  23. Augugliaro, V., Kisch, H., Loddo, V., López-Muñoz, M. J., Márquez-Álvarez, C., Palmisano, G., Palmisano, L., Parrino, F., and Yurdakal, S., "Photocatalytic Oxidation of Aromatic Alcohols to Aldehydes in Aqueous Suspension of Home Prepared Titanium Dioxide 2. Intrinsic and Surface Features of Catalysts," Appl. Catal. A, 349, 189-197 (2008). https://doi.org/10.1016/j.apcata.2008.07.038
  24. Nolan, N. T., Synnott, D. W., Seery, M. K., Hinder, S. J., Wassenhoven, A. V., and Pillai, S. C., "Effect of N-doping on the Photocatalytic Activity of Sol-gel $TiO_{2}$," J. Hazard. Mater., 211-212, 88-94 (2012). https://doi.org/10.1016/j.jhazmat.2011.08.074
  25. Madarasz, J., Braileanu, A., Crişan, M., and Pokol, G., "Comprehensive Evolved Gas Analysis (EGA) of Amorphous Precursors for S-doped Titania by in situ TG-FTIR and TG/DTAMS in Air: Part 2. Precursor from Thiourea and Titanium(IV)- n-butoxide," J. Anal. Appl. Pyrol., 85, 549-556 (2009). https://doi.org/10.1016/j.jaap.2008.10.017
  26. Boulinguiez, B., Bouzaza, A., Merabet, S., and Wolbert, D., "Photocatalytic Degradation of Ammonia and Butyric Acid in Plug-flow Reactor: Degradation Kinetic Modeling with Contribution of Mass Transfer," J. Photochem. Photobiol. A, 200, 254-261 (2008). https://doi.org/10.1016/j.jphotochem.2008.08.005
  27. Li, D., Xiong, K., Yang, Z., Liu, C., Feng, X., and Lu, X., "Process Intensification of Heterogeneous Photocatalysis with Static Mixer: Enhanced Mass Transfer of Reactive Species," Catal. Today, 175, 322-327 (2011). https://doi.org/10.1016/j.cattod.2011.04.007
  28. Arsac, F., Bianchi, D., Chovelon, J. M., Ferronato, C., and Herrmann, J. M., "Experimental Microkinetic Approach of the Photocatalytic Oxidation of Isopropyl Alcohol on $TiO_{2}$. Part 1. Surface Elementary Steps Involving Gaseous and Adsorbed $C_{3}$ $H_{2}O$ Species," J. Phys. Chem. B, 110, 4202-4212 (2006). https://doi.org/10.1021/jp055342b
  29. Den, W., and Wang, C. C., "Enhancement of Adsorptive Chemical Filters via Titania Photocatalysts to Remove Vapor-phase Toluene and Isopropanol," Sep. Purif. Technol., 85, 101-111 (2012). https://doi.org/10.1016/j.seppur.2011.09.054
  30. Demeestere K., Dewulf J., and Van Langenhove H., "Heterogeneous Photocatalysis as an Advanced Oxidation Process for the Abatement of Chlorinated, Monocyclic Aromatic and Sulfurous Volatile Organic Compounds in Air: State of the Art," Crit. Rev. Environ. Sci. Technol., 37, 489-538 (2007). https://doi.org/10.1080/10643380600966467
  31. Liu B., and Zhao X., "A Kinetic Model for Evaluating the Dependence of the Quantum Yield of Nano-TiO2 Based Photocatalysis on Light Irradiance, Grain Size, Carrier Lifetime, and Minority Carrier Diffusion Coefficient: Indirect Interfacial Charge Transfer," Electrochimica Acta, 55, 4062-4070 (2010). https://doi.org/10.1016/j.electacta.2010.01.087