Table 3: ANOVA for removal of lead from aqueous solution using tartrate-Mg-Al layered double hydroxide.

SourceDegree of freedomSum of squaresMean square value

Model1424350.421739.3230.86<0.0010
Residual15845.4356.36
Lack of fit10845.4284.5448309.97<0.0010
Pure error50.008750.00175
Total2925195.86
Time ( )18.548.540.150.7025
pH ( )110371.7210371.72184.02<0.0010
Dosage ( )14516.084516.0880.13<0.0010
Concentration ( )119.3319.330.340.5668