Separation and Determination of Fe(III) and Fe(II) in Natural and Waste Waters Using Silica Gel Sequentially Modified with Polyhexamethylene Guanidine and Tiron

Table 2

Results of Fe(III) and Fe(II) determination in model solutions using minicolumn ().

Added, μg		Length of colored zone, mm		Found, μg
Fe(III)	Fe(II)	Fe(III)	Fe(II)	Fe(III)	Fe(II)
—	5.0	—	10 ± 1	—	5.0 ± 0.5
5.0	—	10 ± 1	—	5.0 ± 0.5	—
1.0	5.0	2 ± 1	10 ± 1	1.0 ± 0.5	5.0 ± 0.5
2.0	5.0	4 ± 1	10 ± 1	2.0 ± 0.5	5.0 ± 0.5
5.0	1.0	10 ± 1	2 ± 1	5.0 ± 0.5	1.0 ± 0.5
5.0	2.0	10 ± 1	4 ± 1	5.0 ± 0.5	2.0 ± 0.5
5.0	5.0	10 ± 1	10 ± 1	5.0 ± 0.5	5.0 ± 0.5