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(一)比較超臨界流體萃取法和索氏萃取法－飛灰之多苯環芳香族碳氫化合
物之研究多苯環芳香族碳氫化合物 ( 簡稱 PAHs)。 大部分由碳氫化合物
不完全燃燒及裂解所產生。因具有致癌性危險，故在環境中含量之多寡對
人體健康影響甚大。研究目的為萃取飛灰中之 PAHs，並探討超臨界流體
萃取和索氏萃取法方法之比較。由初步的實驗結果得到超臨界流體系統之
最佳化操作參數。在比較不同基質的 PAHs 萃取回收率，以石英砂為基質
的萃取效果均高於飛灰基質。探討添加方式，得到直接添加法的 PAHs萃
取回收率大於均勻混合化添加方式。索氏萃取法中，以不同的萃取溶劑
( 苯、二氯甲烷 ) 萃取，苯的 PAHs 萃取回收率優於二氯甲烷溶劑。
(二)以高效能液相層析儀分離四氯酚同分異構物之研究氯酚化合物早期曾
廣泛使用於工業用途，及農業殺生物劑上，如木材防腐劑、消毒劑等。因
其具有毒性及擴散性，且為致癌物，加上不易分解的特性，且由於氯酚化
合物中氯取代基數目越多，生物抑制性愈高。以高效能液相層析儀 /紫外
光偵測器之方式，並配合二種不同性質的管柱(PRP-1, ACT-1)，分離三種
四氯酚 (2,3,4,5 四氯酚，2,3,4,6四氯酚，2,3,5,6四氯酚 ) 同分異構
物。並探討緩衝溶液的 pH 、溶質濃度、溫度變化對分離效果的影響。由
初步的結果得到使用 ACT-1 管柱分離四氯酚，分離條件為 90% 氰甲烷
/10% 醋酸緩衝溶液 (pH=3.87,50mM)，溫度 55℃，流速為 1ml/min 時
，可完全將三種四氯酚同分異構物分離。且在 pH值較高時，由於四氯酚
的溶離現象，故在 PRP-1 管柱和 ACT-1管柱上可見到二個的波峰，其四
氯酚化合物溶離的程度乃由 pH 值來控制。在不同的pH 值中，滯留時間
的變化十分明顯， pH 在 3.87 時，滯留時間最長；pH 值偏酸或偏鹼時
，滯留時間縮短。且溫度增高和溶質濃質增加時均會縮短滯留時間。
(1) Comparison of Supercritical Fluid Extraction and Soxhlet
Extraction of Polynuclear Aromatic Hydrocarbons in Fly Ash PAHs
are formed during the combustion process and adsorbed on fly
ashes in the cooler parts of the stack. Since many PAHs
compounds exhibit carcinogenic or cocarcinogenic properties.
Therefore, analysts of PAHs in fly ash are very important. In
this study, for pretreatment of samples will be compared two
different extraction method- Soxhlet and SFE extraction.
Extraction PAHs in fly ash is experimental purpose. In primary
study, we can find optimization of system operated parameters.
Recovery of quartz sand matrix is higher than fly ash matrix in
different extraction method. Recovery of spiking spot method is
higher than spiking slurry method. Extraction recovery of
benzene is above methylene chloride in Soxhlet extraction
method. (2) Seperation of Three Tetrachlorophenol Isomers by
High-Performance Liquid Chromatography In this study, the
selectivity of three tetrachlorophenol isomers (2,3,4,5-TeCP,
2,3,4,6-TeCP, 2,3,5,6-TeCP) were investigated on two polymer
column (PRP-1 and ACT-1). The effects of various acetonitrile/
buffer mixture, and pH of the buffer solution, and temperature
of the separation columns,and solute concentration of buffer
solution were studied. In this study, tetrachlorophenol isomers
have been separated. An ACT-1 polymer C18 column and an
acetonitrile: ammonium acetate (pH=3.87, 50mM) (90: 10) eluent
are used. We fine two peaks in chromatogram when injected
single standard compound.retention time was reduced by elevated
temperature and increasing solute concentration. In pH study,
the retention time is the longest when pH=3.87, more acid or
more base the retention time was shorted. Accordingly, pH=3.87
was chosen as the optimal value based up on practical
considerations.
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