Table 2.

Experimental matrix for the 2^6-2 design for the extraction.

SFE processing parameters
Runs	Factors
	A	B	C	D	E	F
1	−1	−1	−1	1	−1	1
2	−1	1	1	−1	−1	−1
3	−1	−1	−1	−1	−1	−1
4	−1	1	1	1	−1	1
5	−1	−1	1	−1	1	1
6	0	0	0	0	0	0
7	1	−1	−1	1	1	1
8	1	−1	−1	−1	1	−1
9	1	−1	1	−1	−1	1
10	−1	−1	1	1	1	−1
11	1	1	−1	−1	−1	−1
12	1	−1	1	1	−1	1
13	−1	1	−1	1	1	1
14	1	1	1	−1	1	1
15	0	0	0	0	0	0
16	1	1	−1	1	−1	−1
17	−1	1	−1	−1	1	1
18	1	1	1	1	1	1

A = pressure, B = temperature, C = processing time, D = material.

E = sonication time and F = stirring rate. Row 6 and 15 are the central points.