Table 2:
values and main effects of the variables for both oxalic acid-Fe
3
O
4
systems with purely linear models.
Equation
Magnetite
, —
, mg/L
acid
, mg/L
(
5
)
Synthetic
0.983
3367.0
17680.0
(
7
)
Industrial
0.746
4658.5
5200.0