Optimization Studies on Recovery of Metals from Printed Circuit Board Waste

Table 9

ANOVA quadratic model for copper.

Source	Sum of squares	DOF	Mean square	value	value
Model	7763.50	9	862.61	155.08	<0.0001	Significant
A-CD	4608.00	1	4608.00	828.40	<0.0001
B-solvent	544.50	1	544.50	97.89	<0.0001
C-time	1922.00	1	1922.00	345.53	<0.0001
AB	1.0000	1	1.0000	0.1798	0.6827
AC	225.00	1	225.00	40.45	0.0002
BC	25.00	1	25.00	4.49	0.0668
A^2	184.36	1	184.36	33.14	0.0004
B^2	279.27	1	279.27	50.21	0.0001
C^2	9.82	1	9.82	1.77	0.2206
Residual	44.50	8	5.56
Lack of fit	44.50	3	14.83
Pure error	0.0000	5	0.0000
Total	7808.00	17