Screening of Factors Influencing the Adsorption of Methylene Blue Aqueous Solution onto Raw Maize Cobs Using Fractional Factorial Design

Fractional factorial design is used to identify the significant variables that have large effects on the COD reduction and decolorization of methylene blue dye aqueous solution, through adsorption process. Four factors (pH, adsorbent dosage, temperature, and contact time) were screened by using the 24 fractional factorial designs. The results showed that all the main factors have first-order interaction effects and second-order interaction effect, which were significantly affecting decolorization and COD reduction. Results obtained indicated that fractional factorial design can be used as a method to screen a large number of factors and to reduce the number of experimental runs.