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1.
Zusammenfassung Es wird eine Methode zur Gewinnung von Antimontellurit Sb2(TeO3)3·5 H2O beschrieben. Seine Thermostabilität wurde mittels thermischer, thermo-gravimetrischer, phasenröntgenographischer sowie chemischer Analyse studiert und festgestellt, daß die Entwässerung im Temperaturbereich 50–220° C stattfindet, wobei die Geschwindigkeit dieses Prozesses ein Maximum bei 145° C aufweist. Das erhaltene Tellurit dissoziiert bei 505°C zu TeO2 und Sb2O3 (bzw. Sb2O5).
Preparation and thermostability of the chalkogenates of antimony and bismuth, III; Preparation and thermostability of antimony tellurite
A method is described for the preparation of antimony tellurite Sb2(TeO3)3·5 H2O. Its thermal stability has been studied by thermal, thermo-gravimetric, phase-roentgenographic, and chemical analysis. It was found that desiccation takes place with in the temperature range of 50–220°, the rate of this process displaying a maximum at 145°C. The obtained tellurite dissociates at 505° C to TeO2 and Sb2O3 (Sb2O5, resp.).


Mit 2 Abbildungen  相似文献   

2.
Grinding a mixture of hydrous amorphous chromium oxide (Cr2O3·nH2O), vanadium oxide (V2O5) and antimony oxide (Sb2O5) was conducted by using a planetary ball mill, to investigate their mechanochemical reactions to form chromium vanadium oxide (CrVO4) and chromium antimony oxide (CrSbO4). The synthesis reactions proceed with an increase in grinding periods of time. The ground samples consist of agglomerates with particle size of about ten nanometers. The synthesized CrVO4 sample exhibits a rutile-type tetragonal crystal structure, which is a high pressure phase. Additionally, solid solutions, CrV1−xSbxO4 (x=0∼1, Δx=0.25), have been synthesized mechanochemically from the mixtures of Cr2O3·nH2O, V2O5 and Sb2O5.  相似文献   

3.
Sb/ZSM-5 was obtained by solid-state reaction with the mixture of Sb2O3 and zeolite HZSM-5 under a dry nitrogen flow at 773 K. Characterization of the treated zeolite was undertaken with XRD, 27Al MAS NMR, BET, TGA and FT-IR. The results revealed that part of the antimony oxides migrated into the channels of zeolite, and decreased the Brönsted acid sites in Sb/ZSM-5 remarkably. The other part of antimony oxides together with the amorphous alumino-silicate in the products distributed on the external surface of zeolite ZSM-5 and modified it, while the framework of ZSM-5 in crystal phase was retained. The structure of occluded antimony oxide inside the channels of ZSM-5 was studied by XRD Rietveld method. The result showed that their structure can be described as a chain of non-perfect [Sb5O5(H2O)2]n5n+, which is parallel to the straight channel of ZSM-5. There is about 0.6 [Sb5O5(H2O)2]5+ unit in every cell of the ZSM-5 on an average.  相似文献   

4.
Previous reports of the thermal behaviour of antimony trioxide show significant disagreement on the values for the temperatures associated with specific thermal events. In this reappraisal, samples of both polymorphs of Sb2O3 (senarmontite and valentinite) have been analysed using X-ray diffraction and simultaneous differential thermal/thermogravimetric analysis techniques. The senarmontite-valentinite phase transition has been observed to occur as a multi-stage event commencing at temperatures as low as 615±3 °C—evidence of oxidation to Sb2O4 under inert atmosphere may indicate that the depression is related to surface- or bulk-bound water. Valentinite produced by mechanical milling of senarmontite exhibits the reverse phase transition to senarmontite at a lower than normal temperature (445±3 °C). Oxidation temperatures of 531±4 °C for senarmontite and 410±3 °C for mechanically derived valentinite were also recorded.  相似文献   

5.
The solid-state reactions in the system Cu—Sb—O were investigated by thermogravimetry and X-ray diffraction. Equimolar mixtures of CuO and Sb2O3 form Cu(II)Sb2O6 when slowly heated in air up to 1000°C. The firt step in this reaction is the oxidation of Sb2O3 to Sb2O4 at 380–500°C, followed by further oxidation of Sb2O4 and the formation of CuSb2O6 at 500–1000°C. Thermal decomposition of CuSb2O6 in a flowing nitrogen atmosphere occurs in three stages; the first, with an activation energy of 356 kJ mole?1, results in the formation of a new copper(I) antimony oxide, with a composition of Cu4SbO4.5, as determined by atomic absorption analysis and X-ray fluoresecence. Confirmation of predominantly monovalent copper and pentavalent antimony in the new compound was by ESR and ESCA, respectively. Two forms of Cu4SbO4.5 have been distinguished; one of these (form II) has a structure of lower symmetry, and decomposes when heated in air at 600°C to a mixture of CuO and another new copper antimony oxide, as yet uncharacterized. On further heating to 1100°C in air, Cu4SbO4.5 (form I) gradually reforms. Details of these reactions are summarized and X-ray powder data presented for Cu4SbO4.5.  相似文献   

6.
 The hydrolysis of SbCl3 in hydrochloric acid solution (2.0 mol dm-3 HCl) at 0 °C yields an amor-phous product consisting of uniform spherical particles (d∼0.5 μm), which on continuous aging at the same temperature transform to larger crystals, indicated by XRD to be Sb4O5Cl2. In contrast, in the same solution kept at 25 °C crystalline particles of the same composition form directly after an induction period and then grow with time. The final products, obtained at 0 °C and 25 °C consist of aggregated subunits. These powders on calcination in nitrogen are converted to Sb2O3 and in air to Sb2O4. Received: 23 June 1997 Accepted: 1 July 1997  相似文献   

7.
张兰  尉继英  赵璇  李福志  江锋 《物理化学学报》2001,30(10):1923-1931
90Sr 是核电站放射性废液中需要重点去除的核素之一,水合锑氧化物Sb2O5·mH2O可以在酸性条件下选择性吸附脱除90Sr. 本文在以醇为溶剂的无水体系中,以化学性能较稳定且毒性低的SbCl3为原料,以紫外线照射辅助双氧水氧化及控制水解两步法制备出自掺杂型锑氧化物Sb(Ⅲ)/Sb2O5. 文中采用X射线光电子能谱(XPS)、X射线衍射(XRD)和傅里叶变换红外(FTIR)光谱对材料结构进行结构表征,并采用批量实验方法研究不同Sb(Ⅲ)/Sb(total)比例与Sr(Ⅱ)吸附性能的相关性,以及溶液pH 值对Sr(Ⅱ)吸附性能的影响. 实验结果表明:Sb(Ⅲ)可在较大的比例范围内共存于立方烧绿石型Sb2O5晶格内,形成良好的固溶体Sb(Ⅲ)/Sb2O5;制备过程中通过控制醇溶剂的类型、氧化剂的添加方式以及两步反应温度,可以获得具有不同氧化率,即不同Sb(Ⅲ)/Sb(total)比例的Sb(Ⅲ)/Sb2O5材料;其中Sb(Ⅲ)/Sb(total)比例为49.8%的锑氧化物材料吸附性能最好,在纯水体系下对Sr(Ⅱ)的分配系数为6.6×107 mL·g-1,在pH=3-13 范围内对Sr(Ⅱ)具有良好的吸附性能,并且在本文实验条件下,Sr(Ⅱ)在锑氧化物材料上的吸附更好地符合Langmuir吸附模型.  相似文献   

8.
Perfluorinated 1-isopropyl-, 1-methyl-1-isopropyl-, and 1-methyl-2-isopropylbenzocyclobutenes isomerize under the influence of antimony pentafluoride to perfluorinated alkylstyrenes and alkylindans. The process may be accompanied by dealkylation and also by fluorination and defluorination of the products. With antimony pentafluoride at 50°C perfluoro-1-methyl-1-isopropylbenzocyclobutene gives perfluoro-,,,o-tetramethylstyrene, which isomerizes under the influence of antimony pentafluoride at 130°C into perfluoro-1,2,2-trimethylindan, and the latter forms perfluoro-2,3-dimethylindene under the reaction conditions. Perfluoro-1-methyl-2-isopropylbenzocyclobutene is not changed in the presence of antimony pentafluoride at 50°C but isomerizes to perfluoro-1-isopropylindan at 90°C. The latter is transformed under these conditions into the above-mentioned tetramethylstyrene. Perfluoro-1-isopropylbenzocyclobutene does not react with antimony pentafluoride at 130°C, but at 170°C it gives a mixture of perfluorinated 2,2-dimethylindan, 2,3-dimethylindene, 2,3-dimethyl-4,5,6,7-tetrahydroindene, and 2-isobutyltoluene, which is converted into perfluoro-o-xylene under the reaction conditions.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1419–1424, June, 1992.  相似文献   

9.
SbxOy clusters are produced by using a gas aggregation technique. Antimony vapor is mixed with He/O2 or He/N2O and cooled in a reaction channel. After photoionisation with a KrF (248 nm) or ArF (193 nm) excimer laser the products are mass analyzed in a time of flight mass spectrometer. In the presence of N2O no oxide clusters besides SbO+ can be detected, while with oxygen under similar experimental conditions dramatic changes can be observed. At low oxygen partial pressure the obtained spectra are dominated by the pure Sb x + clusters with low intensity of SbxO y + , whereas at high oxygen partial pressure antimony oxides following the general sequence SbO+(Sb2O3)n are most abundant. The same stable species can furthermore be produced via aggregation of vaporised solid antimony oxide (Sb2O3). Within these experiments another new Series of antimony oxides tentatively assigned to (Sb2O3) n + appeared in the mass spectra.  相似文献   

10.
《Electroanalysis》2006,18(11):1121-1125
In this work, a new approach named “capillary melt method” was developed to fabricate micro antimony wires, and the wire surface was then oxidized in a nitrate melt at high temperature to obtain an antimony/antimony oxide pH electrode. Characterization results show that the oxide layer on the wire surface is porous, and consists of Sb2O3 crystal phase. The pH electrode, made using this method, showed good sensing performance in buffer solutions in the tested pH range of 2–12. Its EMF signal was found to have a linear relationship with pH value of the solution, with a sensitivity of 54.1 mV/pH and a fitting correlation coefficient of R2=1.00. The advantages of the electrode are long‐term stability, fast response, reproducibility and low cost.  相似文献   

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