Dissolution of Metals from Biosolid-Treated Soils by Organic Acid Mixtures
Table 10
Kinetics constant for metal dissolution reaction extracted by organic acid (OA) mixtures according to (1) and (2).
Biosolid treatment (Mg ha−1)
Metal extracted by OAs
Zero- and first-order kinetics constant
Cd
Cr
Cu
Ni
Pb
Zn
Control
0.001 M
0.01
0.11
0.04
0.09
0.43
0.09
0.24
0.12
n.d.
n.d.
1.2
0.12
0.01 M
0.03
0.10
0.06
0.09
1.40
0.09
1.56
0.14
n.d.
n.d.
7.8
0.13
0.1 M
0.08
0.12
0.44
0.08
7.88
0.07
4.28
0.12
0.06
0.09
21.2
0.13
135
0.001 M
0.22
0.09
0.28
0.09
3.44
0.09
2.12
0.12
0.84
0.09
15.8
0.11
0.01 M
0.72
0.12
0.92
0.08
8.84
0.09
6.28
0.12
0.24
0.09
85.6
0.13
0.1 M
3.16
0.13
3.64
0.09
30.4
0.08
26.8
0.14
1.28
0.08
400
0.13
1,080
0.001 M
1.24
0.10
1.36
0.09
9.64
0.08
10.1
0.14
0.52
0.08
100
0.12
0.01 M
4.64
0.10
3.40
0.08
42.8
0.07
39.2
0.12
1.36
0.08
416
0.12
0.1 M
6.68
0.07
5.84
0.08
81.2
0.08
64.4
0.12
3.08
0.08
820
0.10
Values represent means of two replicates. The differences of first-order kinetics constant for Cd among the treatments were tested by one-way ANOVA. In each column, values followed by the same lowercase letter were not significantly different at . Obtained at Moreno Field Station of the University of California, Riverside, CA. From 1976 through 1981, composted biosolids were applied at dry weight rates of 0 (control), 22.5, and 180 Mg ha−1 yr−1, respectively. Concentration was below detection limits of the AAS for Pb = 0.001 mg kg−1.
