- 期刊
GC-AED分析汽油餾分中含硫成分之最適條件探討
Optimization of Sulfur Detection in Low Sulfur Gasoline Fractions with GC-AED
摘要
以氣相層析儀－原子發射偵檢器（GC-AED）分析低硫汽油餾分時，硫層析圖中常出現負向的信號及一些小的正向信號。這些信號造成分析之困擾。本探討之目的在於選擇適當之反應氣體（Reagent Gas）－氫氣及氧氣壓力使硫之選擇性（Selectivity）及靈敏度（Sensitivity）同時增加，避免上述之困擾。本探討應用單形最適化方法（Simplex Optimization Method），經15次實驗，找出最佳條件；硫訊號增強為原條件之2.6倍，硫相對於碳之選擇性增加為原條件之13.8倍。接著應用反應曲面法（Response Surface Method, RSM）進行一組13個實驗，由實驗結果可求得在最佳條件附近之實驗模式（Empirical Model），由實驗模式則可進一步瞭解氫氣及氧氣壓力對於硫分析靈敏度及選擇性之影響。應用最佳分析條件分析數種汽油或汽油摻配餾分（硫含量5~180ppm）之硫層析圖，可以看出非常明顯之改善。
並列摘要
Small negative and positive peaks often appear when analyzing low sulfur gasoline fractions with GC-AED. It is hard to tell whether these signal are sulfur signals or interferences from carbon. This study tried to choose best reagent gas (oxygen and hydrogen) pressure to enhance both sensitivity and selectivity. By using sequential simplex method, the best condition was found within 15 experiments. The sulfur signal increased 2.6 times while the selectivity increased 13.8 times. To further understand the influence of reagent gas pressure on selectivity and sensitivity, response surface method was used to obtain the empirical models. The sulfur chromatgrams with optimized condition show significant improvement in sulfur detection.