Adsorption of silver from aqueous solution onto fly ash and phosphogypsum using full factorial design



The aim of this research is to analyze the role of experimental factors on the adsorption of silver from an aqueous solution by using 24 factorial design. The experimental factors and their respective levels that were selected include an initial silver concentration of 50–250 mg/L, an adsorbent dosage of 1.25–10 g/L, a temperature of 20–60°C, and material types that consist of fly ash and phosphogypsum. The results were statistically analyzed by using the student's t-test, analysis of variance (ANOVA), and an F-test to define important experimental factors and their levels. A regression model that considers the significant main and interaction effects was suggested. The selected experimental factors were determined to influence the adsorption process but their importance varied according to the sequence: initial concentration (50 mg/L) > waste material type (fly ash) > adsorbent dosage (10 g/L) > temperature (60°C). © 2010 American Institute of Chemical Engineers Environ Prog, 2010