Table 1:
Independent variables and their levels in the experimental design.
Independent Variable
Symbols
Unit
Code Levels
-
-
-
-1.68 (-α)
-1
0
1
1.68 (+α)
Time
A
min
39.55
60
90
120
140.45
Temperature
B
ᵒC
49.77
60
75
90
100.23
Solvent concentration
C
%
36.36
50
70
90
103.64