Solar UV-Assisted Pretreatment of River Water Samples for the Voltammetric Monitoring of Nickel and Cobalt Ultratraces

Table 4

Determination of the recovery rate for nickel (II) in 0 hours irradiated (Original Sample), 6 and 12 hours solar UV irradiated (SoUV Sample), and 6 hours artificial UV irradiated (UV Sample).

Nickel	Concentration before spiking (𝜇gL^−1)	Spiked concentration (𝜇gL^−1)	Concentration after spiking (𝜇gL^−1)	Recovered concentration (𝜇gL^−1)	Recovery rate (%)
Original Sample	1.66	5.00	6.05	4.39	87.80
6 h SoUV Sample	2.12	5.00	6.66	4.54	90.80
12 h SoUV Sample	2.62	5.00	7.38	4.76	95.20
UV Sample	2.71	5.00	7.66	4.95	99.00
Blank	0.00	5.00	5.02	5.02	100.48