Levels

Variable

Coding

−1.68 (−α)

−1

0

1

+1.68 (+α)

Catalyst loading (wt%)

X₁

0.26

0.4

0.6

0.8

0.96

Reaction temperature (˚C)

X₂

46.6

50

55

60

63.4

Reaction time (min)

X₃

46

60

80

100

114