The Analysis of Orange Oil and the Aqueous Solubility of d-Limonene. Two Complementary Gas Chromatography Experiments

• Kathryn R. Williams ^[1] ; Russell E. Pierce ^[1]
  1. [1] University of Florida

     University of Florida

     Estados Unidos

     
• Localización: Journal of chemical education, ISSN 0021-9584, Vol. 75, Nº 2 (February), 1998, págs. 223-226
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • The monoterpene d-limonene is determined by gas chromatography using anisole as the internal standard. Unknowns for the orange oil analysis are prepared by diluting commercially available Valencia oil with n-hexane (ca. 2% oil by weight). Students determine the d-limonene content from the GC results and divide by the known d-limonene content of Valencia oil (95.03 %) to obtain the wt% oil in the unknown. In the experiment, students determine the concentration of d--limonene in the head-space vapors above aqueous samples containing varying amounts of d--limonene. The concentration in the vapor levels off at the solubility limit. At the University of Florida, the experiments are performed in the beginning analytical (orange oil analysis) and physical chemistry (solubility determination) laboratories, but they are also applicable to other laboratory courses.