Pyrolysis of cobalt and caesium doped cationic ion-exchange resin

The aim of this study is to monitor the residual content of carbon, sulphur, cobalt and caesium from a cationic ion-exchange resin, Amberlite IRN 77, under pyrolysis. Resin samples were heated at five temperatures (350, 385, 400, 150 and 550 degrees C), under nitrogen atmosphere for 30 min. For the commercial resin (undoped resin), a high residual carbon content (96% at 400 degrees C and 90% at 550 degrees C) was observed, in contrast with the residual sulphur content (33% at 350 degrees C and 23% at 550 degrees C). In the presence of cobalt and caesium, a decreased carbon content (91% at 400 degrees C and 65% at 550 degrees C) and, on the other hand, an increased sulphur content (74% at 350 degrees C and 48% at 550 degrees C) were found. As far as doped elements are concerned, a 'critical temperature' of 400 degrees C seems to be a limit beyond which it is impossible to guarantee that 100% of these two elements remain within the solid residue. (C) 2000 Elsevier Science B.V. All rights reserved.