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Chemistry. Biology. Ecology

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Extraction-Photometric Determination of Cobalt (II) with Hydroxytiophenols and Hydrophobic Amines

Zalov Ali Zal oglu, Azerbaijan State Pedagogical University
Ibragimova Shakhla Adalat Kyzy, Бакинский государственный университет

The possibility of using hydroxythiophenols (HTP) for the photometric determination of cobalt (II) has been studied. Aminophenols (AP) were used as hydrophobic amine: 2- (N,N-methylamino methyl)-phenol (AP1) and 2- (N, N-methylaminomethyl) -4-methylphenol (AP2). Dichloroethane, chloroform and carbon tetrachloride turned out to be the best extractants. With a single extraction with chloroform, 97.5–99.5% of cobalt is recovered as a complex. The cobalt (II) complex is extracted into chloroform in the pH range of 3.6–6.3. Cobalt complexes with HTP and AR are stable in aqueous and organic solvents, do not decompose for two days and after extraction do not break down for more than a month. Maximum optical density is achieved within 5 minutes. The complex is stable when heated to 80° C. The results of studying the ratio Vaq / Vorg for extracting Co (II) in the form of a MLC showed that the optimum Vaq/Vorg is 5/5–80/5. The maximum analytical signal with the complex ation of cobalt with HTP and Am is observed at 540–565 nm. The molar absorption coefficient is (2.62–3.01)?104. The ratio of components in the complexes is Co: HTP: AP = 1:2:2. According to the Nazarenko method it has been established that the complexing form of cobalt is Co2+. At the same time, the number of hydrogen atoms displaced by them from one HTP molecule turned out to be 1. Extracts of cobalt complexes obey the basic law of light absorption at a concentration of 1.25–20 ?g/ml. Based on the results of spectrophotometric studies of cobalt (II) with HTP and AP methods for determining cobalt in different objects have been developed.

  1. Sadovnikova L. K., Orlov D. S., Lozanovskaya I. N. Ekologiya i okhrana okruzhayushchey sredy pri khimicheskom zagryaznenii [Ecology and environmental protection during chemical pollution]. Moscow, Vysshaya shkola Publ., 2006. 334 p. (in Russian).
  2. Marchenko Z., Bal’tsezhak M. K. Metody spektrofotometrii v UF i vidimoy oblastyakh v neorganicheskom analize [Spectrophotometry methods in the UV and visible regions in inorganic analysis]. Moscow, Binom. Laboratoriya znaniy Publ., 2007. 711 p. (in Russian). 
  3. Umland F., Yansen A., Tirig D., Vyunsh G. Kompleksnyye soyedineniya v analiticheskoy khimii [Complex compounds in analytical chemistry]. Moscow, Mir Publ., 1975. 286 p. (in Russian).
  4. Peshkova V. M., Sovostina V. M. Analiticheskaya khimiya nikelya [Analytical chemistry of cobalt]. Moscow, Nauka Publ., 1966. 200 p. 
  5. Makhijani R. M., Barhate V. D. Development of extractive spectrophotometric deter mi na tion of cobalt (II) with [N-(O-hydroxy benzylidene)pyridine-2-amine]. Int. J. of Scientifi c and Research Publications, 2016, vol. 6, no. 4, pp. 108–111.
  6. Ciftci H. Solid phase extraction method for the determination of cobalt in water samples on duolite XAD761 resin using 4-(2-Pyridylazo) resorcinol by FAAS. Current Analytical Chemistry, 2010, vol. 6, no. 2, pp. 154–160. 386 Научный отдел Изв. Сарат. ун-та. Нов. сер. Сер. Химия. Биология. Экология. 2019. Т. 19, вып. 4
  7. Kuliev K. A., Verdizadeh N. A., Suleymanova G. S. Spectrophotometric determination of cobalt (II) with 2, 6-dithiolphenol and its derivatives in the presence of hydrophobic amines. American Journal of Chemistry, 2016, vol. 6, no. 4, pp. 95–103.
  8. Racheva P. V., Gavazov K. B., Lekova V. D., Dimitrov A. N. Complex formation in a liquid-liquid extraction system containing cobalt (II), 4-(2-pyridylazo) resorcinol, and nitron. Journal of Materials, vol. 2013, 7 pages.
  9. Divarova V. V., Gavazov K. B., Lekova V. D., Dimitrov A. N. Spectrophotometric inves tigations on liquid-liquid extraction systems containing cobalt, 4-(2-pyridylazo)- resorcinol and tetrazolium salts. Chemija, 2013, vol. 24, no. 2, pp. 81–87.
  10. Bulatov M. I., Kalinkin I. P. Prakticheskoye rukovodstvo po fotokolorimetricheskim i spektrofotometricheskim metodam analiza [A practical guide to photocolorimetric and spectrophotometric methods of analysis]. Leningrad, Khimiya Publ., 1986. 432 p. (in Russian).
  11. Ioffe B. V., Kostikov R. R., Razin V. V. Fizicheskiye metody opredeleniya stroyeniya organicheskikh soyedineniy [Physical methods for determining the structure of organic compounds]. Moscow, Vysshaya shkola Publ., 1984. 336 p. (in Russian).
  12. Anisimova N. A. Identifi katsiya organicheskikh soyedineniy [Identifi cation of organic compounds]. GornoAltaysk, RIO Gorno-Altayskogo gosuniversiteta, 2009. 118 p. (in Russian).
  13. Nazarenko V.A., Biryuk E.A. Study of the chemistry of the reactions of ions of multivalent elements with organic reagents. J. of Analytical Chemistry, 1967, vol. 22, no. 1, pp. 57–64.
  14. Nazarenko V. A. Vzaimodeystviye ionov mnogovalentnykh elementov s organicheskimi reagentami [Interaction of ions of multivalent elements with organic reagents]. Tr. komis. po analit. khimii AN SSSR [Transactions of the Commission for Analytical Chemistry of the USSR Academy of Sciences]. Moscow, Nauka Publ., 1969. Vol. 17. P. 22.
  15. Dorokhova Ye. N., Prokhorova G. V. Analiticheskaya khimiya (fi ziko-khimicheskiye metody analiza) [Analytical chemistry (physicochemical methods of analysis)]. Moscow, Vysshaya shkola Publ., 1991. 250 p. (in Russian).
  16. Sharp G. A., Soomro G. A. Spectrophotometric determination of cobalt(II) as complexes with brompirogallol red in micellar media. J. of the Chemical Society of Pakistan, 2006, vol. 22, no. 5, pp. 444–447.
  17. Praktikum po agrokhimii: ucheb. posobiye [Practikum on Agrochemistry: Textbook]. 2nd ed., recycled. and add. Ed. V. G. Mineev. Moscow, Izd-vo MGU, 2001. 689 p. (in Russian).