Selective recovery of volatile flavour compounds using reversed-phase polystyrene adsorbents

✍ Scribed by Maik Gehrke; Ulrich Krings; Ralf G. Berger

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 165 KB
• Volume: 15
• Category: Article
• ISSN: 0882-5734
• DOI: 10.1002/(sici)1099-1026(200003/04)15:2<108::aid-ffj876>3.0.co;2-4

✦ Synopsis

Thermodynamically and kinetically controlled adsorption capacities of derivatized polystyrenes were compared to a commercial polystyrene resin (Amberlite 1 XAD 16), a strong acid, cationic exchanger (Amberlite 1 200), and a silica gel (Silikagel 100) using the binary model systems (À)-limonene/(À)-carvone and (À)-a-pinene/(À)-borneol. Functionalization with 2 2SCH 3 , 2 2Br, 2 2B(OH) 2 , 2 2NO 2 , or 2 2SO 3 Na decreased the overall adsorption capacity. Preferred adsorption of (À)-carvone to (À)-limonene was achieved with the sulphonated resin in the aqueous phase. Salting-out experiments showed that the inevitable competition of water molecules dominated, and that (À)-limonene adsorption remained to be kinetically favoured. In n-hexane, however, both (À)-carvone and (À)-borneol were preferentially adsorbed, with loadings 10 times higher than in water with 300 g/l NaCl added. (À)-Borneol loads on Amberlite 200 were only one quarter of the sulphonated XAD 16, and Silikagel 100 was not suitable for multiple adsorption/desorption cycles.