Term Effect Coef SE Coef T* P**
Constant   71.12 0.4284 166.03 0.000
Main Factors  
X -25.53 -12.77 0.4284 -29.80 0.000
pH 15.90 7.95 0.4284 18.56 0.000
BD 24.08 12.04 0.4284 28.10 0.000
Interaction of two factors  
X.pH 9.75 4.87 0.4284 11.38 0.000
X.BD 15.05 7.53 0.4284 17.57 0.000
pH.BD -13.87 -6.93 0.4284 -16.19 0.000
Interaction of three factors  
X.pH.BD -8.11 -4.05 0.4284 -9.46 0.000
*T= t-test, **P=Propabiliy level
Table 3: Statistical parameters for full 23 factorial design of Cd2+ biosorption.