以固定於載體上之掺金屬改質的二氧化鈦分解TNT溶液之探討

Photocatalytic Degradation of TNT Using Immobilized Nanocomposite of TiO2 with Metal Ions in Aqueous Solution

張筱娟(Hsiao-Chuan Chang)

指導教授 ： 曾添文

國立臺北科技大學/工程學院/化學工程所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00026

摘要

以溶凝膠(sol gel)法及氣凝膠(aerogel)法，合成奈米級二氧化鈦，並加入不同金屬離子(銀、鎳、鈀、鋰)加以改質，探討其作為TNT溶液的光催化分解之效率比較。以SEM測試所合成的TiO2顆粒大小，以XRD鑑定晶相及特性峰，以元素分析儀(EDS)分析鈦與掺入金屬之數量比及分佈情形。由分解低濃度(32 ppm)TNT溶液時，顯示以sol gel-TiO2-M(M=Ag，Li)在30分鐘時，分解率皆可達92.5 %，但在分解高濃度(103 ppm)溶液， sol gel-TiO2-Ag在60分鐘時，分解率可達78.8 %；若光照90分鐘後，即可達到91.5 %分解率。
進一步將TiO2固定於載體上，以玻璃布及玻璃絨為載體合成固定化TiO2觸媒，再以其作光催化效率比較。由實驗發現取玻纖布上被覆TiO2觸媒，對TNT廢液(32 ppm)作光照裂解，在60分鐘時僅達66.1 %。若先以aerogel合成掺銀的微小TiO2粉末，再將其摻合懸浮於另一TiO2的sol gel中，最後將其含浸附著於玻璃絨上(外徑約11-13 μm)，經煅燒後，採懸浮式光照裂解高濃度（112 ppm）TNT溶液，60分鐘時分解率達70.3 %，若改以三階段(每階段20分鐘)連續方式光催化高濃度(117 ppm)TNT，光照60分鐘分解率達75.0 %。因此，本研究中，嘗試將TiO2予以固定化，並還能達到75 %的光催化裂解TNT成果。

關鍵字

二氧化鈦 ； 溶凝膠 ； 氣溶膠 ； 光觸媒 ； 奈米顆粒

並列摘要

The sol-gel and aerogel methods were used to prepare TiO2 nanoparticles and their compositions and properties were modified with metal ions, such as silver, nickel, palladium and lithium ions. These nanocomposite materials act as photocatalysts for the degradation of TNT in aqueous solution. The sizes and crystal phases of the TiO2 composites were examined by SEM, PXRD methods, respectively. Under low concentration of TNT (32 ppm), the sol gel-Ag/TiO2 catalyst exhibited that the rate of photocatalytic degradation of TNT for 30 minute irradiation was 92.5%. Whereas, the degradation rate of TNT by sol gel-Ag/TiO2 for 60 minute irradiation was 78.8% at high concentration of TNT (103 ppm). Prolonging the irradiating time to 90 minutes, the cracking ratio of TNT increased to 91.5%.
Glass cloth- and glass fiber-immobilized catalysts were prepared and their photocatalytic degradation efficiency of TNT in aqueous solution was investigated. Under low concentration of TNT (32 ppm), the Ag-TiO2/glass-cloth sample exhibited an efficiency of 66.1% for 80 minute irradiation. However, aero-sol gel-Ag/TiO2/glass-fiber immobilized catalyst showed a degradation rate of TNT of 70.3% for 60 minutes irradiation at high concentration of TNT (112 ppm). By following three-step irradiation (20 minute irradiation for each step), the aero-sol gel-Ag/TiO2/glass-fiber immobilized catalyst exhibited a degradation ratio of 75.0% at high concentration (117 ppm) of TNT.

並列關鍵字

Aerogel ； Nano particles ； Photocatalysis ； Sol-gel ； Titanium dioxide

參考文獻

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