Statistical Optimization of Bioleaching for Simultaneous Recovery of Cu, Sn, Pb, and Zn from Computer-Printed Circuit Boards

Table 6

The ANOVA table for the model to predict percent of leaching of zinc and lead.

Source	Model to predict percent of leaching of zinc					Model to predict percent of leaching of lead
	Sum of squares	df	Mean square	F value	value Prob > F	Sum of squares	df	Mean square	F value	value Prob > F
Model	55.19	9	6.13	26.32	0.0001	61.97	9	6.89	22.06	0.0002
A-time	1.62	1	1.62	6.95	0.0336	7.32	1	7.32	23.44	0.0019
B-temp	11.57	1	11.57	49.66	0.0002	1.26	1	1.26	4.02	0.0848
C-pulp den	2.31	1	2.31	9.92	0.0162	0.8978	1	0.8978	2.88	0.1337
AB	5.76	1	5.76	24.73	0.0016	1.81	1	1.81	5.80	0.0469
AC	2.43	1	2.43	10.45	0.0144	1.99	1	1.99	6.37	0.0396
BC	18.06	1	18.06	77.55	<0.0001	24.80	1	24.80	79.46	<0.0001
A^2	1.48	1	1.48	6.35	0.0399	3.53	1	3.53	11.30	0.0121
B^2	1.55	1	1.55	6.67	0.0363	7.39	1	7.39	23.67	0.0018
C^2	9.32	1	9.32	40.00	0.0004	13.08	1	13.08	41.89	0.0003
Residual	1.63	7	0.2329			2.18	7	0.3121
Lack of fit	1.28	3	0.4272	4.90	0.0794	0.9167	3	0.3056	0.9639	0.4916
Pure error	0.3488	4	0.0872			1.27	4	0.3170
Cor total	56.82	16				64.15	16