甲基第三丁基醚（MTBE）量測分析與輻射分解機制之探討

The Measurement and Radiolysis of MTBE

謝玲鈴(Ling-Ling Hsieh)

指導教授 ： 羅俊光

國立清華大學/原子科學院/生醫工程與環境科學系/博士(2006年)

摘要

本研究利用不?袗?罐採樣法結合GC/MS量測加油站空氣中MTBE及揮發性有機化合物（VOCs），同時以輻射技術分解水中MTBE，並探討其反應機制。
研究發現加油站周界空氣中除含高濃度MTBE 外，亦可量測到Toluene、ethyne 、isobutene 、n-butane 等物種，而且這些化合物濃度均較一般交通路口高。未加裝油氣回收設備的加油站，其周界總VOCs與MTBE的濃度約為加裝油氣回收設備加油站7.3倍與20 倍。在MTBE對於生殖系統的傷害方面，無回收系統的加油站的附近居民所承受MTBE的終生致癌風險度，高於一般可接受度。
此外，本研究以頂空固相微萃取(HS-SPME)搭配GC/FID分析技術配合高科技輻射分解技術，詳盡探討不同輻射因子對於水中MTBE的分解效率，並進一步探討水中MTBE輻射分解的反應機制。研究結果顯示MTBE在59.7Gy/min照射劑量率照射五分鐘，可被完全分解。TBF、TBA、acetone及MA為主要降解中間產物。這些中間產物之最高濃度可分別達MTBE濃度的47％、11％、6.4％及9.1％。有機化合物苯的存在，會降低MTBE的輻射分解效率。另外，重金屬銅的存在，雖對MTBE分解沒有明顯影響，然而卻對其分解中間產物TBF有抑制作用。

關鍵字

甲基第三丁基醚 ； 周界空氣 ； 加油站 ； 輻射分解

並列摘要

This study aims to measure MTBE and volatile organics (VOCs) in the ambient air and using ionizing radiation to degrade MTBE in water. Canister sampling with GC/MS analyzed MTBE and VOCs in the ambient air around gasoline stations during rush hours and assessed their impact on human health. Results from this study clearly indicate that methyl tert-butyl ether (MTBE), toluene,ethyne , isobutene, and n- butane are the major VOCs. Moreover, the concentrations of these compounds in the ambient air near gasoline stations are remarkably higher than those sampled on traffic roads, revealing that these compounds are mainly released from gasoline stations. The concentrations of MTBE and VOCs near the gasoline stations without vapor recovery systems are about 20 and 7.3 times higher than those around the gasoline stations having the recovery systems. The risk of MTBE to the reproductive systems at the sites without vapor recovery system was higher than the normal acceptable values.
The radiolytic degradation of MTBE in aqueous solution was studied under different conditions. Moreover, in this experiment, using Headspace-SPME coupling GC/FID determine the degradative products. Results show that complete degradation of MTBE can be achieved within 5 min of irradiation at 59.7Gy/min. Tert-butyl formate (TBF), tert-butyl alcohol (TBA), acetone, methyl acetate (MA) were found to be the primary intermediates of the degradation reaction with yields of 47%, 11%, 6.4% and 9.1%, respectively. However, the removal of MTBE is significantly decreased with increasing concentration of benzene. In addition, the presence of cupric ions appears to reduce degradation of TBF, while the removal of MTBE is not significantly affected.

並列關鍵字

MTBE ； ambient air ； gasoline station ； radiolysis

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