Solvent Extraction of Sodium Permanganate by Mono-benzo 3m-Crown-m Ethers (m = 5, 6) into 1,2-Dichloroethane and Nitrobenzene: a Method which Analyzes the Extraction System with the Polar Diluents

Analytical equations were derived for the extraction of univalent metal salts (MA) by crown ethers (L) into polar diluents. Then, NaMnO4 was extracted at 25 C by benzo-15-crown-5 and -18-crown-6 ethers (B15C5 and B18C6) from a water (w)-phase into a 1,2-dichloroethane (DCE)-one. So, the extraction constants of Kex1 and Kex2 were determined, where Kex1 = [NaLMnO4]DCE/[Na][L]DCE[MnO4] and Kex2 = [NaL]DCE[MnO4]DCE/[Na][L]DCE[MnO4] (= Kex1/KNaLMnO4). From the calculation processes of these Kex values, KD,MnO4 and KMLA values with MLA = NaLMnO4 were obtained and also KNaL values were estimated from the thermodynamic cycle of KML = Kex2/KD,MKD,A. Here, the KMLA, KD,A or KD,M, and KML values denote an ion-pair formation constant of MLA in the DCE-phase, a distribution constant of A or M between the wand DCE-phases, and a complex formation one of a complex ion ML in the DCE-phase, respectively. The same values were obtained for the w/nitrobenzene (NB) extraction systems. By comparing the KNaL and KD,NaL (= [NaL]NB/[NaL]: distribution constant into NB) values with those previously-reported by other methods, the validity of the equations was confirmed. Additionally, extraction-abilities of the extraction systems with DCE and NB were examined, using component equilibrium constants reported before.