vuzbiochemiИзвестия вузов. Прикладная химия и биотехнологияProceedings of Universities. Applied Chemistry and Biotechnology2227-29252500-1558ИРНИТУ10.21285/achb.974GKTMGLvuzbiochemi-1453Research ArticleХИМИЧЕСКИЕ НАУКИCHEMICAL SCIENCESФазообразование в тройных системах оксидов натрия, редкоземельного металла (скандия, индия, иттербия) и бораPhase formation in ternary systems of sodium, rare-earth (scandium, indium, and ytterbium), and boron oxideshttps://orcid.org/0000-0002-1674-283XСубанаковА. К.SubanakovA. K.

Субанаков Алексей Карпович, к.х.н., заведующий лабораторией; старший преподаватель

670047, г. Улан-Удэ, ул. Сахьяновой, 6;

670000, г. Улан-Удэ, ул. Смолина, 24а

Alexey K. Subanakov, Cand. Sci. (Chemistry), Head of the Laboratory; Senior Lecturer

6, Sakhyanova St., Ulan-Ude, 670047;

24a, Smolin St., Ulan-Ude, 670000

subanakov@binm.bscnet.ruhttps://orcid.org/0000-0003-1301-1983КовтунецЕ. В.KovtunetsE. V.

Ковтунец Евгений Викторович, научный сотрудник

670047, г. Улан-Удэ, ул. Сахьяновой, 6

Evgeniy V. Kovtunets, Researcher

6, Sakhyanova St., Ulan-Ude, 670047

kovtunets@binm.ruhttps://orcid.org/0009-0006-2286-1380СоболевА. Н.SobolevA. N.

Соболев Андрей Николаевич, лаборант

670000, г. Улан-Удэ, ул. Смолина, 24а

Andrey N. Sobolev, Laboratory Assistant

24a, Smolin St., Ulan-Ude, 670000

Sobolevan02@mail.ruhttps://orcid.org/0009-0005-9826-6070ТанхаеваА. С.TankhaevaA. S.

Танхаева Алтана Сергеевна, ведущий инженер

671510, пос. Багдарин

Altana S. Tankhaeva, Lead Engineer

Bagdarin village, 671510

zandeeva02@mail.ruБайкальский институт природопользования СО РАН; Бурятский государственный университет им. Доржи БанзароваРоссияBaikal Institute of Nature Management, Siberian Branch of the Russian Academy of Sciences; Banzarov Buryat State UniversityRussian FederationБайкальский институт природопользования СО РАНРоссияBaikal Institute of Nature Management, Siberian Branch of the Russian Academy of SciencesRussian FederationБурятский государственный университет им. Доржи БанзароваРоссияBanzarov Buryat State UniversityRussian FederationАО «Хиагда»РоссияAO KhiagdaRussian Federation202531052025152158–166Copyright © Субанаков А.К., Ковтунец Е.В., Соболев А.Н., Танхаева А.С., 20252025Субанаков А.К., Ковтунец Е.В., Соболев А.Н., Танхаева А.С.Subanakov A.K., Kovtunets E.V., Sobolev A.N., Tankhaeva A.S.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://vuzbiochemi.elpub.ru/jour/article/view/1453

Целью проведенного исследования являлось изучение фазовых равновесий в системах Na2O–R2O3–B2O3 (R = In, Sc, Yb). Взаимодействия в системах изучались методом твердофазных реакций. Впервые изучено фазообразование в тройных системах оксидов натрия, редкоземельного металла (скандия, индия, иттербия) и бора в субсолидусной области в интервале температур 700–750 °С. Построены предварительные триангуляции изученных систем. Изотермические сечения систем Na2O–R2O3–B2O3 (R = In, Sc, Yb) при 750 °С представлены восемью, тринадцатью и одиннадцатью треугольниками сосуществующих фаз соответственно. В ходе работы в системе Na2O–Sc2O3–B2O3 нами подтверждено образование трех известных двойных боратов натрия-скандия следующих составов: Na3Sc(BO3)2, Na3Sc2(BO3)3, NaScB2O5. Установлено образование двойного бората натрия-скандия ориентировочного состава Na3ScB8O15, которое проиндицировалось в моноклинной сингонии (ориентировочная пространственная группа симметрии Сс). Уточнение параметров элементарной ячейки проведено методом Ле-Бейля: a = 12,625(6), b = 7,725(2), c = 10,409(3), β = 53,19(2)°. Система Na2O– Yb2O3–B2O3 содержит три новых двойных бората: составов Na3Yb(BO3)2, Na3YbB8O15 и состава, близкого к стехиометрическому соотношению Na2O•Yb2O3•B2O3. Впервые экспериментально показано образование соединений: Na3YbB8O15 изоструктурного Na3GdB8O15 и Na3Yb(BO3)2 изоформульного, но не изоструктурного Na3Y(BO3)2. Тройная оксидная система с индием оказалась эвтектичной, то есть без образования двойных боратов натрия-индия.

The study was aimed at examining phase equilibria in Na2O–R2O3–B2O3 systems (R = In, Sc, Yb). Interactions in these systems were analyzed using the solid-state reaction method. Phase formation in the ternary systems of sodium, rare-earth (scandium, indium, and ytterbium), and boron oxides was studied for the first time in the subsolidus region within the temperature range of 700–750°С. Preliminary triangulation of the analyzed systems was conducted. At 750°С, the isothermal cross sections of Na2O–R2O3–B2O3 (R = In, Sc, Yb) systems are represented by eight, thirteen, and eleven triangles of coexisting phases, respectively. The study confirmed the formation of three known double sodium-scandium borates in the Na2O–Sc2O3–B2O3 system: Na3Sc(BO3)2, Na3Sc2(BO3)3, and NaScB2O5. Also, a double sodium-scandium borate of approximate composition Na3ScB8O15 was found to form, which was indexed as monoclinic (approximate space symmetry group Cc). The unit cell parameters were refined using the Le Bail method: a = 12.625(6); b = 7.725(2); c = 10.409(3), β = 53.19(2)°. The Na2O–Yb2O3–B2O3 system contains three new double borates: Na3Yb(BO3)2, Na3YbB8O15, and borate with a composition close to the stoichiometric ratio Na2O•Yb2O3•B2O3. The formation of the following compounds was first experimentally shown: Na3YbB8O15 isostructural to Na3GdB8O15 and isoformula Na3Yb(BO3)2, which is not isostructural to Na3Y(BO3)2. The triple oxide system with indium was found to be eutectic, i.e., without the formation of double sodium-indium borates.

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The authors declare that there are no conflicts of interest present.