Kenny D V, Olesik S V
Department of Chemistry, Ohio State University, Columbus 43210, USA.
J Chromatogr Sci. 1998 Feb;36(2):59-65. doi: 10.1093/chromsci/36.2.59.
A comparison among modified and unmodified supercritical fluid extraction (SFE), enhanced-fluidity liquid extraction, and accelerated solvent extraction (ASE) techniques was made for the extraction of polynuclear aromatic hydrocarbons (PAHs) from an aged, spiked lignite coal fly ash. All of the attempted extraction conditions allowed the extraction of the PAHs to some degree, but no single extraction technique proved to be superior for all of the PAHs used. Three groups of PAHs with similar extraction efficiencies were identified. The group with the lowest molecular weights was best recovered using a 90% CO2-10% methanol mixture at 70 degrees C and 238 atm. The group of medium-molecular-weight PAHs was recovered equally well using any of three extraction conditions: SFE (100% CO2, 90 degrees C, and 238 atm), enhanced-fluidity liquid mixture (60% CO2-40% methanol, 70 degrees C, and 238 atm), and a methanol ASE mixture. The group of high-molecular-weight PAHs seemed to be equally well recovered with all of the attempted extraction conditions, but the enhanced-fluidity conditions (60% CO2-40% methanol, 70 degrees C, and 238 atm) had extraction recoveries (> 85%) with the lowest standard deviations (approximately 5%).
对改良和未改良的超临界流体萃取（SFE）、增强流动性液体萃取和加速溶剂萃取（ASE）技术进行了比较，以从老化的、加标褐煤粉煤灰中萃取多环芳烃（PAH）。所有尝试的萃取条件都能在一定程度上萃取出PAH，但没有一种萃取技术被证明对所有使用的PAH都是最优的。确定了三组萃取效率相似的PAH。分子量最低的一组PAH在70℃和238个大气压下使用90%二氧化碳 - 10%甲醇混合物能得到最佳回收率。中等分子量的PAH组在以下三种萃取条件中的任何一种下回收率都同样良好：SFE（100%二氧化碳，90℃，238个大气压）、增强流动性液体混合物（60%二氧化碳 - 40%甲醇，70℃，238个大气压）和甲醇ASE混合物。高分子量的PAH组在所有尝试的萃取条件下回收率似乎都同样良好，但增强流动性条件（60%二氧化碳 - 40%甲醇，70℃，238个大气压）的萃取回收率（>85%）具有最低的标准偏差（约5%）。
