title: [Characteristics and mechanism of sodium removal by the synergistic action of flue gas and waste solid].
abstract: The carbon dioxide (CO2) in flue gas was used to remove the sodium in the red mud (RM) , a kind of alkaline solid waste generated during alumina production. The reaction characteristics and mechanism of sodium removal by the synergistic action of CO2 and RM were studied with different medium pH, reaction time and temperature. It was demonstrated that the remove of sodium by RM was actually the result of the synergistic action of sodium-based solid waste in RM with the CO2-H2O and OH(-)-CO2 systems. The sodium removal efficiency was correlated with pH, reaction temperature and time. The characteristics of RM before and after sodium removal were analyzed using X-ray diffractometer (XRD) and scanning electron microscope (SEM), and the results showed that the alkaline materials in the red mud reacted with CO2 and the sodium content in solid phases decreased significantly after reaction. The sodium removal efficiency could reach up to 70% with scientific procedure. The results of this research will offer an efficient way for low-cost sodium removal.
authors.affiliation: School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China. yyrhyw@163.com
authors.forename: Yuan-Rong
authors.initials: YR
authors.lastname: Yi
authors.forename: Min-Fang
authors.initials: MF
authors.lastname: Han
mesh_terms: D000468:Alkalies; D000537:Aluminum Oxide; D002245:Carbon Dioxide / Q000737:chemistry*; D008906:Mining; D012037:Refuse Disposal / Q000379:methods; D012964:Sodium / Q000302:isolation & purification*; D014866:Waste Products
chemical_list: D000468:Alkalies; D014866:Waste Products; D002245:Carbon Dioxide; D012964:Sodium; D000537:Aluminum Oxide