Complex Formation in a Liquid-Liquid Extraction System Containing Cobalt(II), 4-(2-Pyridylazo)resorcinol, and Nitron

Table 3

Spectral characteristics of some extracted in organic solvents Co-PAR complexes*.

Additional reagent(s)	Organic solvent	Molar absorptivity,; L mol^−1 cm^−1	𝜆max, nm	Ref.
Xylomethazoline hydrochloride	Chloroform	4.2×10^4	535	[24]
Diphenylguanidine	Chloroform	5.0×10^4	520–530	[27]
Triphenyltetrazolium chloride	Chloroform	5.0×10^4	515	[36]
Iodonitrotetrazolium chloride	Chloroform	5.2×10^4	515	[36]
Zephiramine	Chloroform	5.8×10^4	520	[28]
Tetradecyl-dimethylbenzyl-ammonium chloride + EDTA	Chloroform	5.9×10^4	520	[35]
Dicyclohexyl-18-crown-6	1,2-dichloroethane	6.0×10^4	515	[26]
Tetraphenylarsonium chloride	Chloroform	(6.0-6.4)×10^4	520	[29]
Tetraphenylphosphonium chloride	Chloroform	(6.0-6.4)×10^4	520	[29]
Nitron	Chloroform	6.0×10^4	520	This work

∗The molar absorptivity of the binary cobalt-PAR complex in aqueous medium is 𝜀₅₁₀=5.6×10⁴ L mol⁻¹ cm⁻¹ [39].