Efficient Removal of 2,4-DCP by Nano Zero-Valent Iron-Reduced Graphene Oxide: Statistical Modeling and Process Optimization Using RSM-BBD Approach

Table 3

ANOVA of the response surface for the quadratic model.

Source	Sum of squares	DF	Mean square	value	value ()
Model	18693.01	14	1335.22	15.95	<0.0001	Significant
(dosage)	6463.52	1	6463.52	77.19	<0.0001
(concentration)	1358.94	1	1358.94	16.23	0.0012
(reaction time)	3836.33	1	3836.33	45.82	<0.0001
(initial pH)	4163.43	1	4163.43	49.72	<0.0001
	4.00	1	4.00	0.0478	0.8301
	32.95	1	32.95	0.3935	0.5406
	95.26	1	95.26	1.14	0.3042
	259.69	1	259.69	3.10	0.1000
	2.45	1	2.45	0.0293	0.8666
	155.13	1	155.13	1.85	0.1950
	826.20	1	826.20	9.87	0.0072
	472.34	1	472.34	5.64	0.0324
	1708.82	1	1708.82	20.41	0.0005
	346.70	1	346.70	4.14	0.0613
Residual	1172.24	14	83.73
Lack of fit	1087.43	10	108.74	5.13	0.0646	Not significant
Pure error	84.81	4	21.20
Cor total	19865.25	28