2-Hydroxy-1-naphthaldehyde-P-hydroxybenzoichydrazone: A New Chromogenic Reagent for the Determination of Thorium(IV) and Uranium(VI)

Table 2

Tolerance limits of foreign ions. Amount of U(VI) taken = 4.760 μg mL⁻¹ pH = 6.0.

Foreign ion	Tolerance limit; (μg mL^−1)	Foreign ion	Tolerance limit	Foreign ion	Tolerance limit; (μg mL^−1)
Tartrate	1480	K(I)	1760	Hg(II)	20
Sulphate	1440	Ca(II)	1560	Ru(III)	20
Phosphate	1430	Mg(II)	1510	Mn(II)	11
Thiosulphate	1200	Na(I)	1450	Zr(IV)	10
Bromide	1200	Ba(II)	1170	Sn(II)	10
Thiourea	1140	Hf(IV)	72	Sr(II)	9
Nitrate	960	W(VI)	55	Cr(VI)	7
Thiocyanate	870	Pb(II)	42	Ni(II)	3, 55^b
Iodide	734	Ti(IV)	40	Cu(II)	2, 65^a
Oxalate	440	Au(III)	40	Co(II)	2, 100^a
Chloride	360	Te(IV)	40	Zn(II)	2, 60^c
Carbonate	300	Cd(II)	34	Bi(III)	0.6, 75^a
Fluoride	290	Se(IV)	31	Fe(II)	0.6, 60^a
EDTA	236	Mo(VI)	29	Al(III)	0.3, 60^a
Ascorbate	190	La(III)	28	Th(IV)	0.3, 70^a
Citrate	136	Pd(II)	22	In(III)	0.4, 50^a
		Ag(I)	22	Ga(III)	0.3, 60^a

Masking agents, ^ain presence of 600 ppm of Tartrate, ^b300 ppm of oxalate, ^c500 ppm of thiocyanate.