在廢水水體中，氨是一種常見的汙染物，當濃度過高時，對水中生物會造成嚴重的危害。一般常見的處理方式為離子交換法及氣提法，但此兩種處理方式需要將水體pH值提升，處理完氨汙染後，會造成額外的水體汙染。
本研究使用鉑改質之二氧化鈦進行光催化處理程序，以高解析度穿透式電子顯微鏡觀察鉑顆粒在二氧化鈦表面的分布情況，以感應耦合電漿原子放射光譜儀檢測鉑擔載量。在模擬魚缸環境的反應器中，在紫外光的照射下，所開發的光觸媒能有效的將低濃度(10 ppm)氨降低至魚類暴露之安全範圍內(3 ppm)。藉由離子層析儀分析進行反應的水體，得知隨著鉑含量的提升，氨降解的反應速率也隨之提升，能將NH4+/NH3完全轉化為低毒性的NO3-。
進一步將光觸媒固定於多孔性載體上進行測試，可知此光觸媒在經過多次反應循環後會出現失活的現象。再將此光觸媒濾材置於實際魚缸系統中應用，並觀察魚類生存狀況與分析水中氨氮含量，以確認此處理程序之可行性。
實際應用於魚缸系統後，發現能有效抑制水中氨濃度上升的速率，與對照組相比較，當應用光觸媒系統時，其魚群數量為對照組兩倍時，其氨濃度仍低於對照組，且硝酸根的濃度隨之提升，可以推測皆由氨經光催化反應而來，並且可有效地提高魚群的存活率。

In the waste water, ammonia is a general pollutant, which severely endanger the aquatics. There are several methods to deal with ammonia, such as stripping an ion exchange. However, the necessary operation in basic conditions of these methods is the major disadvantage for practical application, resulting in the generation of new contaminants.
In this work, the photocatalytic process was carried out by using Pt/TiO2. The morphologies of the Pt on this photocatalyst were obtain by HRTEM and the Pt content was analyzed by ICP-OES. A glass reactor containing variant concentration of ammonia was used to simulate an aquarium. Under UVA irradiation at room temperature, the ammonia was degraded over Pt/TiO2 from 10 to 3 ppm, which is the safe situation for regular fish. The change in concentration of ammonia and other derivatives during reaction was measured by an ion chromatography. The result indicates the degradation rate of ammonia is increased with the increase in Pt content on titania. With the optimization of reaction parameters, total ammonia could be completely converted to the less toxic component, nitrate.
The designed catalyst was immobilized on a porous supports as practical filter. The deactivation phenomenon of this filter was observed after long-time reaction. This filter was further applied in an fish bowl containing 8 Cardinal tetra to evaluate the photocatalytic activity for ammonia degradation.
The result from fish bowl indicates the generation rate of ammonia is suppressed with using this photocatalytic system. Even though the fish bowl equipped photocatalytic system was two times the amount of fish in the control one, the concentration of ammonia in the photocatalytic fish bowl was still lower than that in control one. The increase in the nitrate concentration in the photocatalytic fish bowl resulted from the photocatalytic degradation of ammonia over the prepared filter, meanwhile, the survival rate is also improved.

[1] D. Randall, et al., “Ammonia toxicity in fish”, Marine Pollution Bulletin, vol. 45 pp. 17-23, 2002.
[2] F. L. Briski, et al., “High nitrate removal from synthetic wastewater with the mixed bacterial culture”, Biores. Technol., vol. 96, pp. 879-888, 2005.
[3]Z. Svobodova, et al., “Diagnostic Preventation and Therapy of Fish Diseases and Intoxicationsis Manual”, BN. 80-901087-0-9, pp. 270, 1991.
[4]M. Greeley, “Nitrite Toxicosis In Freshwater Fish "Brown Blood Disease"”, Animal Disease Diagnostic Laboratory, Newsletter, 1998.
[5]F. B. Jensen, “Nitrate Disrupts Multiple Physiological Functions in Aquatic animals”, Comparative Biochemistry and Physiology A : Molecular & Integrative Physiology, vol. 135 pp. 9-24, 2003.
[6] B. Saunier, et al., “Kinetics of Breakpoint Chlorination and Disinfection Sanitary “, Engineering Research Laboratory, College of Engineering and School of Public Health, University of California, 1976.
[7]唐存宏，「工業廢水氨氮處理概述」，財團法人台灣產業服務基金會，2013.
[8] M. de O. Meloa, et al., “Photocatalytic production of hydrogen: an innovative use for biomass derivatives”, Journal of the Brazilian Chemical Society, vol. 22, pp. 1401, 2011.
[9]曾堯宣、黃嘉宏、黃珧玲、劉淑鈴，「奈米光觸媒環境應用原理與實例」，化工技術，第157期，頁103-121，2006.
[10]林有銘，「無所不在的環境清潔工--奈米光觸媒」，科學發展月刊，第408期，頁24-31，2006.
[11] M. Umar, et al., “Photocatalytic Degradation of Organic Pollutants in Water”, Organic Pollutants - Monitoring, Risk and Treatment, pp. 197, 2013
[12]O. Carp, et al., “Photoinduced Reactivity of Titanium Dioxide.” Progess in Solid State Chemsitry, vol. 32, pp. 33-177, 2004.
[13]薛明軒，「鉑改質光觸媒二氧化鈦之紫外光與可見光應答光催化活性」，碩士論文，國立台灣科技大學化學工程系，2011.
[14]N. Wetchakuna, et al., “Influence of calcination temperature on anatase to rutile phase transformation in TiO2 nanoparticles synthesized by the modified sol–gel method”, Materials Letters, vol. 82, pp. 195-198, 2012.
[15]郭建宏，「碳改質二氧化鈦及其可見光應答催化活性之研究」，碩士論文，國立台灣科技大學化學工程系，2010.
[16]李陵杰，「銀-碳共改質二氧化鈦及其紫外光與可見光應答光催化活性之研究」，碩士論文，國立台灣科技大學化學工程系，2012.
[17]Y. Chen, et al., “Promoting effects of H2 on photooxidation of volatile organic pollutants over Pt/TiO2”, New Journal of Chemistry, vol. 29, pp. 1514-1519, 2005.
[18] D. S. Cabral, et al., “Implementation of Schottky Barrier Diodes (SBD) in Standard CMOS Process for Biomedical Applications”, Biomedical Engineering - Technical Applications in Medicine, InTech, DOI: 10.5772/2608, 2012.
[19] Q. Wang, et al., “Synthesis of Ag or Pt nanoparticle-deposited TiO2 nanorods for the highly efficient photoreduction of CO2 to CH4”, Chemical Physics Letters vol. 639, pp. 11-16, 2015.
[20] X. Gong, et al., “Modulating charge transport in semiconductor photocatalysts by spatial deposition of reduced graphene oxide and platinum”, Journal of Catalysis, vol. 332 pp. 101-111, 2015.
[21]D. Hufschmidt et al., “Enhancement of the photocatalytic activity of various TiO2 materials by platinisation”, Journal of Photochemistry and Photobiology A : Chemistry vol. 148, pp. 223-231, 2002.
[22]E. Kowalska, et al., “Modification of Titanium Dioxide with Platinum Ions and Clusters :  Application in Photocatalysis” Journal of Physical Chemistry C, vol. 112, pp. 1124-1131, 2008.
[23] J. Nemoto, et al., “Photodecomposition of ammonia to dinitrogen and dihydrogen on platinized TiO2 nanoparticules in an aqueous solution”, Journal of Photochemistry and Photobiology A: Chemistry, vol. 185, pp. 295-300, 2007.
[24] X. Jiang, et al., “Photocatalytic reforming of glycerol for H2 evolution on Pt/TiO2 : fundamental understanding the effect of co-catalyst Pt and the Pt deposition route, Journal Materials Chemistry A, vol. 3, pp. 2271-2282, 2015.
[25]B. D. Fraters, et al., “How Pt nanoparticles affect TiO2-induced gas-phase photocatalytic oxidation reactions”, Journal of Catalysis, vol. 324, pp. 119-126, 2015.
[26]Y. Hu, et al., “Enhanced photocatalytic activity of Pt-doped TiO2 for NOx oxidation both under UV and visible light irradiation: A synergistic effect of lattice Pt4+ and surface PtO”, Chemical Engineering Journal, vol. 274, pp. 102-112, 2015.
[27]W. Wang, et al., “Superiority and mechanism of Pt oriented-deposition in improving the photocatalytic activity of TiO2 sphere with exposed {001} facet”, Materials Letters, vol. 145, pp. 180-183, 2015.
[28] O. Rosseler, et al., “Structural and electronic effects in bimetallic Pd Pt nanoparticles on TiO2 for improved photocatalytic oxidation of CO in the presence of humidity”, Applied Catalysis B : Environmental, vol. 166–167, pp. 381-392, 2015.
[29] Y. Qin, et al., “Enhanced methanol oxidation activity and stability of Pt particles anchored on carbon-doped TiO2 nanocoating support”, Journal of Power Sources, vol. 278, pp. 639-644, 2015.
[30] Z. Jiang, et al., “Rational removal of stabilizer-ligands from platinum nanoparticles supported on photocatalysts by self-photocatalysis degradation”, Catalysis Today, vol. 242 pp. 372-380, 2015.
[31] A. Rautioa, et al., “Chemoselective hydrogenation of citral by Pt and Pt-Sn catalysts supported on TiO2 nanoparticles and nanowires”, Catalysis Today, vol. 241, pp. 170-178, 2015.
[32] T. Chave, et al., “Sonocatalytic degradation of oxalic acid in the presence of oxygen and Pt/TiO2”, Catalysis Today, vol. 241 pp. 55-62, 2015.
[33] E. Su, et al., “Photocatalytic conversion of simulated EDTA wastewater to hydrogen by pH-resistant Pt/TiO2 reactivated carbon photocatalysts”, Renewable Energy, vol. 75, pp. 266-271, 2015.
[34] X. Fua, et al., “Photocatalytic reforming of biomass: A systematic study of hydrogen evolution from glucose solution” International Journal of hydrogen energy, vol. 33, pp. 6484-6491, 2008.
[35] K. Huang, et al., “Promotion effect of ultraviolet light on NO+CO reaction over Pt/TiO2 and Pt/CeO2–TiO2 catalysts” Applied Catalysis B : Environmental, vol. 179 pp. 395-406, 2015.
[36] X. Yin, et al., “Well-dispersed Pt on TiO2 : A highly active and selective catalyst for hydrogenation of 3-nitroacetophenone”, Applied Catalysis A : General vol. 509, pp. 38-44, 2016.
[37] M. Li, et al., “Photocatalytic decomposition of perfluorooctanoic acid by noble metallic nanoparticles modified TiO2”, Chemical Engineering Journal, vol. 286, pp. 232-238, 2016.
[38]Z. Zhang, et al., “Role of Particle Size in Nanocrystalline TiO2-Based Photocatalysts”, The Journal of Physical Chemistry C, vol. 111, pp. 18724-18730, 2007.
[39]M. Altomare, et al., “High activity of brookite TiO2 nanoparticles in the photocatalytic abatement of ammonia in water”, Catalysis Today, in press, 2014.
[40] K. Obata, et al., “Photocatalytic decompositionof NH3 over TiO2 catalysts doped with Fe”, Applied Catalysis B : Environmental, vol. 160-161, pp. 200-203, 2014.
[41] X. J. Zuo, et al., “The role and fate of inorganic nitrogen species during UVA/TiO2 Disinfection”, Water Research, vol. 80, pp. 12-19, 2015.
[42]宋天祐、曹錫章、王杏橋，「無機化學」，北京高等教育出版社，第三版，頁936，1994.
[43]J. Shi, et al., “Photoluminescene Characteristics of TiO2 and Their Relationship to the Photoassisted Reaction of Water/Methanol Mixture”, The Journal of Physical Chemistry C, vol. 111, pp. 693-699, 2006.
[44]J. Liqiang, et al., “Review of photoluminescence performance of nano-sized semiconductor materials and its relationships with photocatalytic activity”, Solar Energy Materials and Solar Cells, vol. 90, pp. 1773-1787, 2006.
[45]Y. Rao, et al., “Visible Light-Induced Photodegradation of Simazine in Aqueous TiO2 Suspension”, Industrial and Engineering Chemistry Research, vol. 52, pp. 13580-13586, 2013.
[46]C. Kuo, et al., “Photocatalytic mineralization of codeine by UV-A/TiO2－Kinetics, intermediates, and pathways”, Journal of Hazardous Materials, vol. 301, pp. 137-144, 2016.
[47]洪健豪，「以金屬Ni_Pd_Pt修飾氧化鈦奈米管去除水中氨氮之研究」，碩士論文，國立台灣大學環境工程學研究所，2008.
[48]S. Shibuya, et al., “Influence of pH and pH adjustment conditions on photocatalytic oxidation of aqueous ammonia under airflow over Pt-loaded TiO2”, Applied catalysis A : General, vol. 496 pp. 73-78, 2015.
[49]N. Takenaka, et al., “Fast Oxidation Reaction of Nitrite by Dissolved Oxygen in the Freezing Process in the Tropospheric Aqueous Phase”, Journal of Atmospheric Chemistry, vol. 29, pp. 135-150, 1998.
[50]C. Cheng, et al., “Effects of ammonia exposure on apoptosis, oxidative stress and immune response in pufferfish (Takifugo obscurus)”, Aquatic Toxicology, vol. 164, pp. 61-71, 2015.
[51]R, Jia, et al., “Effects of nitrite exposure on haematological parameters, oxidative stress and apoptosis in juvenile turbot (Scophthalmus maximus)”, Aquatic Toxicology, vol. 169, pp. 1-9, 2015.