Kinetic study of the CO2 desorption process by carbonated Na2ZrO3 solid absorbent.

A kinetic study of the CO 2 desorption process by carbonated sodium zirconate (Na 2 ZrO 3 ) synthesized by a liquid suspension route is presented using zirconium acetylacetonate and sodium acetate as precursors. Na 2 ZrO 3 was characterized by XRD, SEM and TGA. Na 2 ZrO 3 exhibited a 90% conversion during absorption with respect to the theoretical value. CO 2 desorption kinetic study used three temperatures; 850, 900 °C and 950 °C and three concentrations: 5, 3 and 1% of CO 2 in Ar at 200 ml/min. XRD data shown only slight segregation of the precursors, which led to a small amount of ZrO 2 formation in the solid product. The global rate of the decarbonation reaction of Na 2 ZrO 3 was of first order in CO 2 concentration and strongly dependent on temperature. The calculated apparent activation energy was E A = 23.35 kcal/mol. Na 2 ZrO 3 performance during four continuous cycles, shown an excellent thermal and chemical stability, with the material conversion remaining practically unchanged. [ABSTRACT FROM AUTHOR]