Trapping Efficiencies of Various Adsorbents in Supercritical Fluid Extraction with Modified Carbon Dioxide

✍ Scribed by Chaudot, X. ;Tambuté, A. ;Caude, Marcel

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 93 KB
• Volume: 21
• Category: Article
• ISSN: 0935-6304
• DOI: 10.1002/(sici)1521-4168(19980301)21:3<175::aid-jhrc175>3.0.co;2-n

✦ Synopsis

One way of collecting extracted analytes after a supercritical fluid extraction (SFE) is to pass the depressurized fluid through a trap composed of a solid adsorbent. The influence of the adsorbent nature on the trap efficiency has been studied. First, the retention factors of each compound of a polarity test mix (tetracosane, naphthalene, fluoranthene, acetophenone, N,N-dimethylaniline, 2-naphthol, decanoic acid) have been determined on five high specific area (greater than 800 m 2 /g) polymeric phases by supercritical fluid chromatography (SFC). The comparison of this values with those obtained on octadecyl silica (ODS) showed that polymeric phases have the greatest retention power. After that, the efficiency of a solid trap filled with the greatest retention power polymeric adsorbent was evaluated by using pure carbon dioxide and 2.5%, 5%, 10%, and 20% methanol-modified carbon dioxide. As expected, this trap permitted a quantitative collection of all the former compounds even when a content as high as 10% of methanol was implemented. A solid trap filled with ODS adsorbent allowed quantitative collection of all the compounds only at a methanol content lower than 2.5%.