Zn2+ + Cd2+ (mg/L)

Zn2+

Cd2+

kobs (h−1)

R2

kobs (h−1)

R2

5 + 5

0.02083

0.81109

0.01234

0.9978

10 + 10

0.02081

0.97056

0.04392

0.9325

20 + 20

0.0138

0.82848

0.0251

0.99336