caa a22 4500 469038551 CHVBK 20180323132803.0 cr unu---uuuuu 170328e19920601xx s 000 0 eng 10.1007/BF00816840 doi (NATIONALLICENCE)springer-10.1007/BF00816840 Complexation reactions of cerium(III and IV) with 9-phenyl-2,3,7- trihydroxy-6-fluorone in the presence of cationic surfactants [Elektronische Daten] [Mohamed Zaki, Nabil Hafez, A. El-Sayed] Komplexierungsreaktionen von Cer(III und IV) mit 9-Phenyl-2,3,7-trihydroxy-6-fluoron in Gegenwart kationischer oberflächenaktiver Stoffe The complexation reactions of cerium(III and IV) with 9-phenyl-2,3,7-trihydroxy-6-fluorone (H3 PF) have been studied in the presence and absence of some surfactants and protective colloids. Maximum enhancement of the chelate absorbances is obtained with the cationic surfactant cetylpyridinium bromide (CPB) or cetyltrimethylammonium bromide (CTAB). In thepH ranges 8.2-9.0 and 9.8-10.8 the ternary 1:3:3 and 1:4:3 cerium(III)-PF-CPB complexes are formed with molar absorptivities of 9.02 × 104 and 9.86 · 104 lmol−1 cm−1 at 570 and 590 nm, respectively. The corresponding 1:4:2 and 1:3:2 complexes of cerium(IV) are formed in thepH ranges 8.4-9.0 and 9.8-10.6 in the presence ofCTAB andCPB, respectively. Their molar absorptivities are 8.00·104 and 8.56·104lmol−1 cm−1 at 570 and 590 nm, respectively. The stability constants of the studied complexes have been determined and a spectrophotometric method has been developed to determine the cerium content in monazite concentrate. Springer-Verlag, 1992 Cerium(III and IV) complexes nationallicence 9-Phenyl-2,3,7-trihydroxy-6-fluorone nationallicence Surfactants nationallicence Zaki Mohamed Department of Chemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt aut Hafez Nabil Hot Laboratory Center, Atomic Energy Authority, Cairo, Egypt aut El-Sayed A. Department of Chemistry, Faculty of Science, Azhar University, Assuot, Egypt aut Monatshefte für Chemie / Chemical Monthly Springer-Verlag 123/6-7(1992-06-01), 477-486 0026-9247 123:6-7<477 1992 123 706 https://doi.org/10.1007/BF00816840 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00816840 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zaki Mohamed Department of Chemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt aut NATIONALLICENCE 700 1- Hafez Nabil Hot Laboratory Center, Atomic Energy Authority, Cairo, Egypt aut NATIONALLICENCE 700 1- El-Sayed A. Department of Chemistry, Faculty of Science, Azhar University, Assuot, Egypt aut NATIONALLICENCE 773 0- Monatshefte für Chemie / Chemical Monthly Springer-Verlag 123/6-7(1992-06-01), 477-486 0026-9247 123:6-7<477 1992 123 706 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer