Optimizing the Extraction Conditions of Hydroxytyrosol from Olive Leaves Using a Modified Spherical Activated Carbon: A New Experimental Design

Table 7

Analysis of variance of the quadratic model in Box-Behnken design.

Source	Sum of squares	df	Mean square	-value	-value
Model	3201,44	9	355,72	70,33	< 0.0001	Significant
A (adsorbent ratio)	1755,58	1	1755,58	347,10	< 0.0001
B (temperature)	34,24	1	34,24	6,77	0,0481
C (time)	741,51	1	741,51	146,60	< 0.0001
AB	9,00	1	9,00	1,78	0,2398
AC	106,61	1	106,61	21,08	0,0059
BC	4,82	1	4,82	0,9526	0,3739
	339,40	1	339,40	67,10	0,0004
	67,09	1	67,09	13,26	0,0149
	214,39	1	214,39	42,39	0,0013
Residual	25,29	5	5,06
Lack of fit	25,29	3	8,43
Pure error	0,0000	2	0,0000
Cor Total	3226,73	14