Mendeleev University of Chemical Technology of Russian, Moscow, Russia:

I. A. Pochitalkina, Professor, Doctor of Technical Sciences, e-mail: pochitalkina@list.ru
A. E. Likhosherst, 1^st year Master’s student

Kurnakov Institute of General and Inorganic Chemistry, Moscow, Russia:

D. F. Kondakov, Senior Researcher, Candidate of Technical Sciences, e-mail: kdf@list.ru

The increase in the rate of extraction and use of rare earth elements (REE) necessitates the study of their environmental and industrial safety. Despite the relatively low content of REEs in phosphate ores (less than 1.5% (wt.)), significant volumes of production of phosphoric acid and mineral fertilizers based on it require environmental monitoring of REEs both in the soil located in the immediate vicinity of phosphogypsum dumps and in the phosphate fertilizers themselves, which are the main source of REEs in it, paying special attention to the irreplaceable soils of greenhouse farms. Inductively coupled plasma mass spectrometry (ICP – MS) occupies the leading position today among the variety of direct methods for the quantitative determination of REEs. However, for a number of domestic producers of phosphate fertilizers, the ICP – MS method is still too complicated and expensive. As an affordable alternative, we can mention the spectrophotometric method (SPM), based on the formation of a colored complex of rare-earth elements with the analytical reagent Arsenazo III. On the example of a sample of phosphorite from the Polpinsky deposit, a comparative assessment of the possibility of quantitative determination of REEs in phosphate raw materials by the ICP – MS method is presented as the most promising, as well as the SPM as the most accessible. It is shown that the sensitivity of the spectrophotometric method is sufficient for the reliable determination of the amount of REEs in the phosphate raw material. The reasons for significant errors in determination of the amount of REEs in phosphate raw materials by the photometric method and possible ways to reduce them to values comparable with the error of the method are considered.

1. Dostal J. Rare Earth Element Deposits of Alkaline Igneous Rocks. Resources. 2017. Vol. 6, Iss. 3. p. 34.
2. Arkhangelskaya V. V., Usova Т. Yu., Lagonskiy N. N., Chistov L. B. Rare earth metal ores in Russia. Mineralnoe syryo. Seriya geologo-ekonomicheskaya. No. 19. Moscow : VIMS, 2006. 72 p.
3. Kisilev Е. А. On the state and use of mineral resources of the Russian Federation in 2019. State report. Moscow, 2020. 494 p.
4. On approval of the Strategy for the development of the mineral resource base of the Russian Federation until 2035: Order of the Government of the Russian Federation dated December 22, 2018 No. 2914. Code: electronic fund of legal and normative-technical documentation. Available at: http://docs.cntd.ru/document (accessed: 14.12.2021).
5. Li X., Chen Z., Zhang Y. et al. A human health risk assessment of rare earth elements in soil and vegetables from a mining area in Fujian Province, Southeast China. Chemosphere. 2013. No. 93. pp. 1240–1246.
6. Zhuang M., Zhao J., Li S. et al. Concentrations and health risk assessment of rare earth elements in vegetables from mining area in Shandong, China. Chemosphere. 2017. No. 168. pp. 578–582.
7. Dabakh Е. V. Rare earth elements in soils of natural and technogenic landscapes of the Kirov region. Teoreticheskaya i prikladnaya ekologiya. 2016. No. 3. pp. 56–67.
8. Alekseenko V. А. Rare chemical elements in soils of landscapes in the south of the European part of Russia. Modern problems of soil pollution: Proceedings of the III International scientific conference. Moscow : Izdatelstvo MGU, 2010. pp. 20–26.
9. Redling K. Rare Earth Elements in Agriculture with Emphasis on Animal Husbandry. Germany : University of Munich, 2006. 360 p.
10. Thomas P. J., Carpenter D., Boutin C., Allison J. E. Rare earth elements (REE): effects on germination and growth of selected crop and native plant species. Chemosphere. 2014. No. 96. pp. 57–66.
11. Balaram V. Rare earth elements: A review of applications, occurrence, exploration, analysis, recycling, and environmental impact. Geoscience Frontiers. 2019. Vol. 10, Iss. 4. pp. 1285–1303.
12. Ladonin D. V. Soil contamination of the Cherepovets industrial region with lanthanides. “Modern problems of soil pollution” Proceedings of the IV Inter national scientific conference. Moscow : Izdatelstvo MGU, 2013. pp. 125–131.
13. Faraz S., Abdollahy M., Petersen J. et al. Leaching and recovery of phosphate and rare earth elements from an iron-rich fluorapatite concentrate: Part II: Selective leaching of calcium and phosphate and acid baking of the residue. Hydrometallurgy. 2018. Vol. 184. pp. 29–38.
14. Damian P. A Literature Review of the Health and Ecological Effects of the Rare Earth Elements. Stand Alone Report. Colorado : Union Blvd, 2014. 51 р.

15. Zhang H., Feng J., Zhu W. et al. Chronic toxicity of rare-earth elements on human beings: implications of blood biochemical indices in REE high regions, South Jiangxi. Biological Trace Element Research. 2000. Vol. 73, No. 1. pp. 1–17.
16. Wang L. et al. Concentrations and distribution patterns of rare earth elements in water body from intertidal flat of Tianjin and influence of various factors. J. Rare Earths. 2004. Vol. 22, No. 6. pp. 896–903.
17. Goecke F., Jerez C., Zacheder V. et al. Use of lanthanides to alleviate the effects of metal ion-deficiency in Desmodesmus quadricauda (Sphaeropleales, Chlorophyta). Frontiers in Microbiology. 2015. Vol. 6, Iss. 2. pp. 1–12.
18. Rim K. T., Koo K. H., Park J. S. Toxicological evaluations of rare earths and their health impacts to workers: A Literature Review. Safety and Health at Work. 2013. Iss. 4. pp. 12–26.
19. Zakharov I. S. On the problem of ecological danger of rare earth metals. Izvestiya SPbGETU “LETI”. 2018. No. 8. pp. 91–97.
20. Yuhui M. Toxicity of cerium and thorium on Daphnia magna. Ecotoxicol Environ Saf. 2016. Vol. 134. P. 226–232.
21. Barenboim G. M., Avandeeva O. P., Korkina D. A. Rare earth elements in aqueous objects (ecological aspects). Voda: khimiya i ekologiya. 2014. No. 5. pp. 42–55.
22. Zhao H. et al. Oxidative injury in the brain of mice caused by lanthanide. Biological Trace Element Research. 2011. Vol. 142. Р. 174–189.
23. Cheng J. Immune dysfunction and liver damage of mice following exposure to lanthanoids. Environ Toxicol. 2014. Vol. 29. Р. 64–73.
24. Li J., Verweij R. A., van Gestel C. A. M. Lanthanum toxicity to five different species of soil invertebrates in relation to availability in soil. Chemosphere. 2018. Vol. 193. P. 412–420.
25. Paasz A., Czekaj P. Toxicological and cytophysiological aspects of lanthanides action. Acta Biochimica Polonica. 2000. Vol. 47, No. 4. P. 1107–1114.
26. Tong S.-L., Zhu W.-Z., Gao Z.-H. et al. Distribution characteristics of rare earth elements in children’s scalp hair from a rare earths mining area in Southern China. Journal of Environmental Science and Health. 2004. Vol. 39, Iss. 9. P. 2517–2532.
27. Li X., Chen Z., Zhang Y. et al. A human health risk assessment of rare earth elements in soil and vegetables from a mining area in Fujian Province, Southeast China. Chemosphere. 2013. Vol. 93, Iss. 3. P. 1240–1246.
28. Kotelnikova А. D., Fastovets I. А., Rogova О. B., Stolbova V. V. Toxicity of lanthanum and cerium under biotest conditions with onions (Alliumcepa). Byulleten Pochvennogo instituta imeni V. V. Dokuchaeva. 2017. No. 89. pp. 54–67.
29. Gorbatenko А. А., Revina Е. I. Instrumental methods for the determination of rare earth elements (Review). Zavodskaya laboratoriya. 2014. Vol. 80, No. 4. pp. 7–19.
30. Zawisza B., Pytlakowska K., Feist B. et al. Determination of rare earth elements by spectroscopic techniques: a review. Journal of Analytical Atomic Spectrometry. 2011. Vol. 26. pp. 2373–2390.
31. Djingova R., Mihaylova V., Lyubomirova V. et al. Multielement analytical spectroscopy in plant lonomics research. Applied Spectroscopy Reviews. 2013. Vol. 48, Iss. 5. pp. 384–424.
32. Astrom M., Corin N. Distribution of rare earth elements in anionic, cationic and particulate fractions in boreal humus-rich streams affected by acid sulphate soils. Water Research. 2003. Vol. 37, Iss. 2. pp. 273–280.
33. Zhang X. C., Nearing M. A., Polyakov V. O. et al. Using rare-earth oxide tracers for studying soil erosion dynamics. Soil Science Society of America Journal. 2003. Vol. 67, Iss. 1. pp. 279–288.
34. Zybinskiy А. М., Kolotov V. P., Karandashev V. К., Kordyukov S. V. Determination of rare-earth and associated elements in niobium-rare-earth ores by inductively coupled plasma atomic emission spectrometry using modeling
calibration and mathematical accounting for interferences. Zhurnal analiticheskoy khimii. 2019. Vol. 74, No. 3. pp. 173–185.
35. Zybinskiy А. М. Determination of the mass fraction of niobium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, yttrium, scandium, strontium, barium, phosphorus, titanium, vanadium, manganese and iron in rare metal and rare earth ores by atomic emission with inductively coupled plasma by the NSAM 544-AES method. Moscow : VIMS, 2016. 32 p.
36. GOST 25702.10–83. Raremetallic concentrates. Method for determination of the sum of rare earths. Introduced: 01.07.1984.
37. Pochitalkina I. A., Artamonova O. A., Vinokurova O. V., Kondakov D. F. Textural and Structural Characteristics of Phosphorites from the Polpinsky Deposit. Russian Journal of Inorganic Chemistry. 2017. Vol. 62, No. 11. pp. 1495–1498.
38. Pochitalkina I. A., Vinokurova O. B., Kondakov D. F. Behavior of impurities of polpinophosphorites in acid extraction. Russian Journal of Inorganic Chemistry. 2018. Vol. 63. No. 5. pp. 583– 586.
39. Pochitalkina I. A., Kondakov D. F., Siromyatnikov A. S., Makaev S. V. Investigation of solid phase behavior during process of acidic decomposition of polpinophosphorite. Izv. Vyssh. Uchebn. Zaved. Seriya : Khim. Khim. Tekhnol. 2017. Vol. 60, No. 10. pp. 47–52.
40. Savin S. B. Organic reagents of the Arsenazo III group. Moscow : Atomizdat, 1971. 350 p.