Preconcentration of Copper Using 1,5-Diphenyl Carbazide as the Complexing Agent via Dispersive Liquid-Liquid Microextraction and Determination by Flame Atomic Absorption Spectrometry

Table 2

Determination of copper in water samples.

Sample	Cu (II) amount (μg L^−1)		Recovery (%)
	Added	Found
Tap water; (drinking water system of Behshahr, Iran)	0.0	n.d.^a	—
	50.0	49.0 (2.6)^b	98.0
	100.0	99.0 (2.5)	99.0
Mineral water; (Damavand mineral water, Iran)	0.0	n.d.	—
	50.0	49.0 (2.5)	98.0
	100.0	96.0 (2.6)	96.0
River water; (Tajan river, Sari, Iran)	0.0	n.d.	—
	50.0	47.5 (2.7)	95.0
	100.0	97.0 (2.5)	97.0
Sea water; (Caspian sea water, Sari, Iran)	0.0	n.d.	—
	50.0	51.5 (2.8)	103.0
	100.0	102.0 (2.8)	102.0

^aNot detected.
^bRSD of three replicate experiments.