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

Table 2

Analytical characteristics of the proposed method.

Element condition	Concentration range (𝜇g L^−1)	Slope	Intercept	𝑅^2	R.S.D. (𝑛=5)^a	LOD^b(𝜇g L^−1)
Co without preconcentration	250–5000	3.97×10^−3	−0.013	0.9871	1.45 (500)	32.0
Co with preconcentration	20.0–100	0.279	+0.008	0.9997	2.22 (20)	0.26
Pb without preconcentration	250–5000	5.03×10^−3	−0.034	0.9972	0.88 (600)	46.0
Pb with preconcentration	20.0–100	0.256	−0.012	0.9989	1.88 (30)	0.44

^aValues in parentheses are the Co and Pb concentrations (𝜇g L⁻¹) for which the RSD was obtained.
^bLimit of detection, calculated as three times the standard deviation of the blank signal.