作業環境PAHs揮發性影響XAD微孔介質採樣吸附之研究

Influence of Volatility on the Collection of Vapor-phase PAHs with XAD Porous Adsorbent in Workplace Measurement

李經民(James J. Lee) ； 汪禧年(Shi-Nian Uang) ； 黃國林(Kuo-Lin Huang) ； 莊智仁(Chih-Jen Chuang)

《勞工安全衛生研究季刊》 14卷2期 (2006/06) Pp. 87-96

https://doi.org/10.7005/JOSH.200606.0087

摘要

本研究藉由微孔介質「吸附相曲線」解析半揮發性有機物(S-VOC)吸附特性，及推估作業環境XAD-4採集PAHs採樣滯留體積(V(下標 R))與安全採樣體積(V(下標 R))。實驗以薄層吸附裝置探討七種半揮發性PAHs（三環：AcPy、AcP、Flu、PA、Ant；四環：Fl、Pyr）微孔介質吸附特性。研究結果顯示XAD-4微孔介質七種氣狀PAHs吸附滯留體積(V(下標 R))與化合物揮發性（P(下標 L))，過冷液蒸氣壓）保持良好相關性(R^2，0.900)，XAD-4單位吸附滯留體積（V(下標 g)；每克介質V(下標 R)值）範圍值25.3~158.8立方公尺，隨PAHs揮發性降低（環數增多）其(V(下標 g))值有明顯上升趨勢。本研究顯示「吸附曲線」有助解析S-VOCs吸附特性，常溫下S-VOCs化合物揮發性本質是影響微孔介質吸附關鍵因子。本研究另估算作業環境XAD採樣管PAH安全採樣體積(V(下標 s))，依據NIOSH採樣方法(2 L/min)XAD-4介質300mg或600mg採樣管，即使採集24小時其安全採樣體積(V(下標 s))明顯大於實際採樣體積(V)不會有破出疑慮。而本研究針對S-VOCs吸附機制與估算其採樣安全體積之探討，已為未來作業環境相關S-VOC採樣吸附討論奠定良好的研究基礎。

關鍵字

作業環境 ； 吸附機制 ； 半揮發性有機物 ； 安全採樣體積

並列摘要

This investigation studies the collection retention of polycyclic aromatic hydrocarbons (PAHs) from a common XAD-4 adsorbent for evaluating vapor-phase PAH sampling efficiency in workplace measurement. Laboratory examinations using frontal adsorption curves were conducted to explore the collection efficiency of seven PAH vapors-acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene-by XAD-4 resin. The results demonstrated a linear regression of retention volumes (V(subscript R)) versus vapor pressure of the compounds. (P(subscript L)) for the adsorption of seven PAHs on XAD-4 adsorbent showed a good correlation (R2, 0.900) The specific retention volumes of PAHs (V(subscript g),V(subscript R)/w, w=weight of adsorbent) increased with decreasing volatility of the compounds at 20℃ (V(subscript g) ranging from 25.3~158.8 M^3). The study revealed that the frontal adsorption approach was helpful in interpreting adsorption characteristics of PAHs with XAD-4 porous adsorbent. Meanwhile, volatility of the compound was a dominant factor in the adsorption of semi-volatile organic compounds (S-VOCs) at ambient temperature conditions (20℃) Based on the NIOSH sampling method for workplace measurement, a safe sampling volume (V(subscript s)) of XAD-4 adsorbent (in the amounts of 300 and 600 mg) relating the theoretical plates of frontal chromatography (N) to adsorptive retention volume (V(subscript R)) of the seven PAHs at 95% and 99% collection efficiencies was estimated.

並列關鍵字

Workplace measurement ； Adsorption mechanism ； Semi-volatile organic compound ； Safe sampling volume

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