Coal fly ash based carbons for SO2 removal from flue gases.
Two different coal fly ashes coming from the burning of two coals of different rank have been used as a precursor for the preparation of steam activated carbons. The performance of these activated carbons in the SO(2) removal was evaluated at flue gas conditions (100 degrees C, 1000 ppmv SO(2), 5% O(2), 6% H(2)O). Different techniques were used to determine the physical and chemical characteristics of the samples in order to explain the differences found in their behaviour. A superior SO(2) removal capacity was shown by the activated carbon obtained using the fly ash coming from a sub-bituminous-lignite blend. Experimental results indicated that the presence of higher amount of certain metallic oxides (Ca, Fe) in the carbon-rich fraction of this fly ash probably has promoted a deeper gasification in the activation with steam. A more suitable surface chemistry and textural properties have been obtained in this case which explains the higher efficiency shown by this sample in the SO(2) removal.
Rubio
B
B
Departamento de Energía y Medioambiente, Instituto de Carboquímica-CSIC, Miguel Luesma Castán 4, Zaragoza, Spain. brubio@icb.csic.es
Izquierdo
M T
MT
D002244:Carbon / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry*; D060729:Coal Ash; D004785:Environmental Pollutants / Q000032:analysis / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D052638:Particulate Matter / Q000737:chemistry*; D013458:Sulfur Dioxide / Q000032:analysis / Q000737:chemistry*; D018505:Waste Management / Q000379:methods*; D014866:Waste Products / Q000032:analysis*
D060729:Coal Ash; D004785:Environmental Pollutants; D005740:Gases; D052638:Particulate Matter; D014866:Waste Products; D013458:Sulfur Dioxide; D002606:Charcoal; D002244:Carbon