Separation of the Components of a Commercial Analgesic Tablet: A Two-Week Sequence Comparing Purification by Two-Base Extraction and Column Chromatography

• Kevin D. Revell ^[1]
  1. [1] Murray State University

     Murray State University

     Estados Unidos

     
• Localización: Journal of chemical education, ISSN 0021-9584, Vol. 88, Nº 10, 2011, págs. 1413-1415
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • A new laboratory experiment is described in which students compare two benchtop separation methods to isolate the three active components of the commercial analgesic Excedrin. In the two-week sequence, aspirin, acetaminophen, and caffeine are separated using either a two-base liquid–liquid extraction or silica column chromatography. Students then evaluate the two separation methods based on percent recoveries and on purity, as determined by thin-layer chromatography. This procedure introduces three important techniques using a single theme. The experiment has been designed to minimize cost of chemicals and hazardous waste generation, while challenging students to critically evaluate the strengths and weaknesses of different purification techniques.