The Solid Phase Extraction of Some Metal Ions Using Palladium Nanoparticles Attached to Silica Gel Chemically Bonded by Silica-Bonded N-Propylmorpholine as New Sorbent prior to Their Determination by Flame Atomic Absorption Spectroscopy

Table 2

Effect of type and concentration of eluting agent on recovery of analytes (𝑁=3).

Eluent conditions	Recovery (%)
	Cd	Co	Fe	Ni	Zn
H2SO4	57.3	100.0	63.1	51.7	44.1
HNO3	12.2	58.2	63.1	49.6	61.8
HCl	67.2	88.0	73.6	80.2	69.8
HClO4	58.3	70.5	100.3	42.4	25.6
HCl 3 M	71.2	85.6	75.1	96.4	63.1
HCl 4 M	82.5	88.6	79.1	88.6	70.6
HCl 5 M	94.5	99.5	102.3	94.5	95.6
HCl 7 M	81.3	83.1	89.6	82.4	66.4
HCl 8 M	80.4	72.5	87.4	70.5	59.1
5 mL HCl 5 M	19.8	40.4	52.6	57.8	56.4
7 mL HCl 5 M	54.0	59.8	64.3	70.5	78.1
8 mL HCl 5 M	97.8	102.0	97.6	103.2	98.6
9 mL HCL 5 M	37.1	69.6	75.6	57.8	87.5
12 mL HCl 5 M	22.9	79.7	89.5	68.4	86.6