Table 3. Effect of Coexisting Ions on the Recoveries of the Determined Metal Ions by Various Adsorbents (pH = 7.0–7.2, n = 5).

		recovery (%)
		TEOS/EDTA		NaSi/EDTA/NH2		TEOS/QAS
ions	C, mg/L	Pb(II)	Cr(III)	Pb(II)	Cr(III)	CrO42–	CrO42–
K(I)	12 000	101 ± 1.3	101 ± 1.9	104 ± 0.8	106 ± 0.3	101 ± 1.3	101 ± 1.9
Na(I)	1000	95 ± 0.9	98 ± 1.4	99 ± 1.5	98 ± 0.4	95 ± 0.9	99 ± 1.3
Ca(II)	5000	95 ± 0.8	92 ± 0.9	96 ± 1.3	99 ± 0.5	95 ± 0.8	102 ± 0.5
Mg(II)	100	84 ± 1.4	90 ± 0.7	94 ± 0.6	87 ± 1.7	84 ± 1.4	101 ± 0.2
Zn(II)	100	84 ± 1.4	90 ± 0.7	94 ± 0.6	87 ± 1.7	84 ± 1.4	100 ± 0.7
Co(II), Ni(II)	10	82 ± 1.1	89 ± 0.6	93 ± 0.7	85 ± 1.4	82 ± 1.1	99 ± 0.9
Cl–	5000	99 ± 0.9	101 ± 1.4	102 ± 1.5	101 ± 0.4	99 ± 0.9	101 ± 1.4
Br–	100	96 ± 0.7	96 ± 0.7	97 ± 1.4	99 ± 0.8	96 ± 0.7	91 ± 0.7
SO42–	5000	95 ± 0.8	92 ± 0.9	98 ± 1.3	99 ± 0.5	95 ± 0.8	92 ± 0.9
HPO42–	5000	99 ± 1.4	98 ± 0.7	99 ± 0.6	97 ± 1.6	70 ± 1.4	91 ± 0.6
NO3–	5000	95 ± 0.9	98 ± 1.4	99 ± 1.5	98 ± 0.7	75 ± 0.9	95 ± 1.0
humic acid	70	99 ± 0.8	97 ± 0.9	98 ± 1.0	96 ± 0.6	99 ± 0.9	96 ± 1.0
fulvic acid	50	95 ± 0.8	95 ± 0.6	97 ± 1.6	97 ± 0.8	95 ± 0.8	95 ± 0.9