Tris(2-Aminoethyl)Amine-Functionalized Fe₃O₄ Magnetic Nanoparticles as a Selective Sorbent for Separation of Silver and Gold Ions in Different pHs

Table 2

Effect of type of eluent on percent recovery of Ag(I) and Au(III) by TREN-Fe₃O₄.

Eluent	Ag recovery, %	Au recovery, %
H2SO4 0.1 M	43.5	51.2
H2SO4 0.5 M	48.7	59.7
H2SO4 1 M	56.4	72.5
HCl 0.1 M	59.2	65.4
HCl 0.5 M	64.8	68.3
HCl 1 M	97.0	81.6
HCl 2 M	98.5	84.1
Thioacetamide 0.1 M + HCl 0.1 M	83.2	67.7
Thiourea 0.1 M + HCl 0.1 M	95.2	86.9
Thiourea 0.1 M + H2SO4 0.1 M	95.3	97
Thiourea 0.1 M + H2SO4 1 M	97.0	99.0

Conditions—Ag: 1 𝜇g mL⁻¹; sample volume: 100 mL; pH: 8.
Au: 1 𝜇g mL⁻¹ sample volume: 100 mL; pH: 2.