A Green Preconcentration Method for Determination of Cobalt and Lead in Fresh Surface and Waste Water Samples Prior to Flame Atomic Absorption Spectrometry

Table 3

Determination of cobalt and lead in certified reference material and water samples.

(a)

Certified reference material	Certified values (𝜇g L^−1)		Measured values (𝜇g L^−1)		Percentage of recovery (RSD %)
	Co	Pb	Co	Pb	Co	Pb
SRM 1643e	27.06±0.3	19.63±0.2	26.8±0.82	19.24±0.5	99.0% (3.06%)	98.0% (2.60%)

(b)

Samples	Added (𝜇g L^−1)		Measured (𝜇g L^−1)		Recovery (%)
	Co	Pb	Co	Pb	Co	Pb
Canal water	0	0	3.34±0.962	6.08±0.781	—	—
	2	2	5.32±0.384	8.06±0.822	99.8	99
	5	5	8.33±0.432	11.0±0.784	100	98.4
	10	10	13.3±0.642	15.9±0.828	99.6	98.2

Mean ± SD (𝑛=3).