An article in Journal of Hazardous Materials [Biosorption of Reactive Dye Using Acid-Treated Rice Husk: Factorial Design

An article in Journal of Hazardous Materials [€œBiosorption of Reactive Dye Using Acid-Treated Rice Husk: Factorial Design Analysis€ (2007, Vol. 142(1), pp. 397€“403)] described an experiment using biosorption to remove red color from water. A 2⁴full factorial design was used to study the effect of factors pH, temperature, adsorbent dosage, and initial concentration of the dye. Handle columns 1 and 2 of the output as blocks.

(a) Estimate the factor effects. Based on a normal probability plot of the effect estimates, identify a model for the data from this experiment.

(b) Conduct an ANOVA based on the model identified in part (a). What are the conclusions?

(c) Analyze the residuals and plot residuals versus the predicted removal efficiency.

(d) Construct a regression model to predict removal efficiency in terms of the actual factor levels.

Transcribed Image Text:

pH Run Dosage (g/L) Concentration Temperature (C) Removal Efficiency (%) (mg/L) 2 50 20 89.36 95.78 5 50 20 53.67 52.02 50 50 20 86.97 93.76 80.55 4 50 50 20 72.39 250 68.46 5 20 64.99 32.44 5 250 20 28.44 50 250 20 93.19 93.69 250 88.17 8. 50 20 91.41 5 50 40 97.25 95.41 10 5 50 40 76.42 56.51 11 50 50 40 76.24 90.83 79.54 73.21 12 50 50 40 13 84.31 5 250 40 82.84 14 5 250 40 53.32 44.96 94.77 15 50 250 40 96.53 89.32 16 50 250 40 90.75 2. 2. 2. 2. 2. 2.