Dissolution of Metals from Biosolid-Treated Soils by Organic Acid Mixtures

Table 13

First-order kinetics constant for metal dissolution reaction extracted by organic acid (OA) mixtures according to (3).

Biosolid treatment	Metal extracted by OAs	First-order kinetics constant ()
		Cd	Cr	Cu	Ni	Pb	Zn
Control	0.001 M	4.71	0.34	4.11	4.87	n.d.	5.00
	0.01 M	3.99	0.30	3.90	3.93	n.d.	5.42
	0.1 M	4.30	0.37	4.49	4.46	0.36	4.92
135 Mg ha^−1	0.001 M	4.13	0.38	4.05	4.65	0.38	5.63
	0.01 M	3.88	0.51	4.03	3.95	0.40	5.33
	0.1 M	3.96	0.48	3.81	3.79	0.50	6.06
1,080 Mg ha^−1	0.001 M	4.93	0.32	4.30	4.81	0.24	4.85
	0.01 M	5.16	0.40	4.41	4.81	0.32	5.75
	0.1 M	6.25	0.37	4.88	5.53	0.43	6.80

Obtained at Moreno Field Station of the University of California, Riverside, CA. From 1976 through 1981 composted BSL 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.