Adsorption of cadmium by sulphur dioxide treated activated carbon.
Merck carbon (1.5 mm) was treated in three ways: heating from ambient temperature to 900 degrees C in SO(2); treatment at ambient temperature in SO(2); or successive treatments in SO(2) and H(2)S at ambient temperature. All samples were then characterised and tested as adsorbents of Cd(2+) from aqueous solution. The characterisation was in terms of composition by effecting ultimate and proximate analyses and also of textural properties by N(2) adsorption at -196 degrees C. Kinetics and extent of the adsorption process of Cd(2+) were studied at 25 and 45 degrees C at pH of the Cd(2+) solution (i.e., 6.2) and at 25 degrees C also at pH 2.0. The various treatments of the starting carbon had no significant effect on the kinetics of the adsorption of Cd(2+), but increased its adsorption capacity. The most effective treatment was heating to 900 degrees C, the adsorption in this case being 70.3% more than that of the starting carbon. The adsorption increased at 45 degrees C but decreased at pH 2.0 when compared to adsorption at 25 degrees C and pH 6.2, respectively.
Departamento de Electrónica e Ingeniería Electromecánica, Escuela de Ingenierías Industriales, Universidad de Extremadura, Avda. de Elvas s/n, 06071, Badajoz, Spain. amacias@materiales.unex.es
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A
Macías-García
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V
Gómez-Serrano
M F
MF
Alexandre-Franco
C
C
Valenzuela-Calahorro
D000327:Adsorption; D002104:Cadmium / Q000493:pharmacokinetics*; D002244:Carbon / Q000737:chemistry*; D007220:Industrial Waste; D012037:Refuse Disposal / Q000379:methods*; D013458:Sulfur Dioxide / Q000737:chemistry*; D013696:Temperature
D007220:Industrial Waste; D002104:Cadmium; D013458:Sulfur Dioxide; D002244:Carbon