Table 5: Variance analysis of the polynomial model of first order for the dairy wastewater treatment by photocatalyst treatment.


CoefficientSE coefficientTP

Constant8.8528.5581.020.382
Reaction time3.7652.8501.320.278
Thickness of ZnO1.8352.8500.640.565
pH−4.6002.850−1.610.205
Effluent concentration −0.2602.850−0.090.933

S = 4.03031, 𝑅 2 = 61.4%, 𝑅 2 (adjusted) = 10.0%.