Absorption and desorption of carbon dioxide in the rare earth oxide-doped Bi2O3 powder

The rare earth oxide-doped Bi2O3 powders were prepared by mechanical alloying (MA) method using a planetary ball-milling machine and their CO2-absorbing/desorbing properties were investigated by TG-DTA. As a result, the sample powders were found to absorb CO2 gas around 400-500 degrees C. However, the CO2-absorption and desorption changed depending on doped rare earth oxide and sample composition; the Y2O3-doped Bi2O3 did not show absorbing and desorbing cycleability at all. Absorbed and desorbed CO2 contents also varied with MA time. In the La2O3-doped Bi2O3, the 72 h MA'ed (Bi2O3)(0.70)(La2O3)(0.30) was found to be the material with highest performance as for CO2 content and cycleability. (c) 2005 Elsevier B.V. All rights reserved.