Neues aus der Chemie des Berylliums Dehnicke, Kurt; Neumüller, Bernhard
Zeitschrift für anorganische und allgemeine Chemie (1950),
12/2008, Volume:
634, Issue:
15
Journal Article
The solubilities in the three-component systems MIO sub(3)-Be(IO sub(3)) sub(2)-H sub(2)O (M = K, NH super(+) sub(4) Rb, Cs) were studied at 25 C by the method of isothermal decrease of ...supersaturation. It has been established that double salts, K sub(2)Be(IO sub(3)) sub(4) times 2H sub(2)O, (NH sub(4)) sub(2)Be(IO sub(3)) sub(4) 2H sub(2)O, and Rb sub(2)Be(IO sub(3)) sub(4) 2H sub(2)O, crystallize from the ternary solutions within wide concentration ranges. Both the X-ray powder diffraction and the spectroscopic studies (infrared and Raman) reveal that the title compounds are isostructural. They crystallize in the monoclinic space group P2/m with lattice parameters: K sub(2)Be(IO sub(3)) sub(4) times 2H sub(2)O - a = 14.218(5)A, b = 6.747(2)A, c = 5.765(2)A, beta = 98.74(4), V = 546.6(2)A super(3); (NH sub(4)) sub(2)Be(IO sub(3)) sub(4) times 2H sub(2)O - a = 14.414(4)A, b = 6.838(2)A, c = 5.947(2)A, beta = 99.52(4), V = 578.0(2)A super(3); Rb sub(2)Be(IO sub(3)) sub(4) times 2H sub(2)O - a = 14.423(4) A, b = 6.867(2) A, c = 5.743(3) A, beta = 98.15(3), V = 562.9(3) A super(3). Infrared spectroscopic experiments show that comparatively strong hydrogen bonds are formed in the potassium and rubidium salts as deduced from the wavenumbers of v sub(OD) of matrix-isolated HDO molecules (isotopically dilute samples) owing to the strong Be-OH sub(2) interactions (synergetic effect). However, the IO super(-) sub(3) ions in the ammonium compound are involved in hydrogen bonds with NH super(+) sub(4) ions additionally to those with water molecules and as a result of these intermolecular interactions the proton acceptor strength of the iodate ions decreases (anti-cooperative effect), thus leading to the formation of weaker hydrogen bonds in this compound (bonds of moderate strength) as compared to those formed in the potassium and rubidium ones. The normal vibrations of other entities (IO super(-) sub(3) ions and BeO sub(4) tetrahedra (skeleton vibrations)) are also discussed.
Mixtures of tritium breeder (lithium) and neutron multiplier (beryllium) are being considered for use in increasing the tritium breeding ratio in breeding blankets. However, lithium and beryllium ...react under normal operating conditions, and therefore, a high-functional tritium breeder such as lithium beryllium oxide (Li sub(2)Be sub(2)O sub(3)) needs to be developed to compensate for this reaction under high-temperatures. LiOH times H sub(2)O and BeO powders were mixed in stoichiometric proportions at a Li/Be molecular ratio of 1.0. The sintering temperature was established as 1073 K by thermogravimetric/differential thermal analysis (TG-DTA). The Li/Be molar ratio of the reaction products measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) after the reaction agreed with the nominal molar ratio obtained by mixing LiOH times H sub(2)O and BeO. Crystal structure analysis of this powder was performed by the XRD technique. The XRD patterns of products were the same as those of Li sub(2)Be sub(2)O sub(3) as listed in the JC-PDF-Card, and no impurities were indicated. The results indicate that the solid-state reaction of LiOH times H sub(2)O and BeO is suitable for synthesizing lithium beryllium oxide (Li sub(2)Be sub(2)O sub(3)).
The Front Cover shows the art gallery within the Beryllium Centre, which exhibits some of the latest samples of beryllium art. The current exhibition features the solid state structure of dinuclear ...(PPh3)BeCl22. In this piece, only one phosphine ligand can be accommodated due to the steric bulk of PPh3. However, two smaller ligands, like PMePh2, can find a place in the Beryllium Centre. Therefore, size restrictions apply with a threshold cone angle from 136° to 145°. This parameter dictates whether single or double admission is allowed. Furthermore, the electron donating abilities of the ligands determine whether they behave as spectator ligands or attack the solvent. Therefore, the walls are covered with advertising flyers by the stronger donors. More information can be found in the Research Article by M. R. Buchner and S. I. Ivlev.
Highly Condensed and Super‐Incompressible Be2PN3 Krach, Georg; Steinadler, Jennifer; Witthaut, Kristian ...
Angewandte Chemie International Edition,
July 15, 2024, Volume:
63, Issue:
29
Journal Article
Peer reviewed
Open access
Although beryllium and its compounds show outstanding properties, owing to its toxic potential and extreme reaction conditions the chemistry of Be under high‐pressure conditions has only been ...investigated sparsely. Herein, we report on the highly condensed wurtzite‐type Be2PN3, which was synthesized from Be3N2 and P3N5 in a high‐pressure high‐temperature approach at 9 GPa and 1500 °C. It is the missing member in the row of formula type M2PN3 (M = Mg, Zn). The structure was elucidated by powder X‐ray diffraction (PXRD), revealing that Be2PN3 is a double nitride, rather than a nitridophosphate. The structural model was further corroborated by 9Be and 31P solid‐state nuclear magnetic resonance (NMR) spectroscopy. We present 9Be NMR data for tetrahedral nitride coordination for the first time. Infrared and energy‐dispersive X‐ray spectroscopy (FTIR and EDX), as well as temperature dependent PXRD complement the analytical characterization. Density functional theory (DFT) calculations reveal super‐incompressible behavior and the remarkable hardness of this low‐density material. The formation of Be2PN3 through a high‐pressure high‐temperature approach expands the synthetic access to Be‐containing compounds and may open access to various multinary beryllium nitrides.
Be‐containing nitrides are sparsely investigated. The herein presented Be2PN3 expands the synthetic approach to highly condensed beryllium nitrides under high‐pressure high‐temperature conditions. The comprehensive analytic combines powder X‐ray diffraction, 9Be and 31P solid state nuclear magnetic resonance spectroscopy as well as infrared spectroscopy, among others. Density Functional Theory calculations reveal super‐incompressible behavior.
The mining of uranium-beryllium ores has resulted in substantial beryllium (Be) contamination. In this study, agricultural waste durian shells were utilized as raw materials to prepare biochar, which ...was further modified to enhance its adsorption capacity (Mn-DSB). The results effectively demonstrated Mn loading onto the DSB surface. Batch experiments were conducted to identify the optimal adsorption conditions of Mn-DSB for beryllium. At a temperature of 35 °C and pH 6, beryllium's maximum adsorption capacity (Qe) was 42.08 mg·g-1. The materials' internal structure was analyzed before and after adsorption via multiple techniques. Mn-DSB manifested potent selectivity towards beryllium in multicomponent mixed solutions, binary systems, and uranium-beryllium wastewater, as the beryllium removal rate exceeded 90%. The study investigated the recyclability of Mn-DSB and found that after five reuse cycles, the adsorption and desorption efficiencies were 90% and 85%, respectively. The strong ligand complexation (N-H, CO32-, -OH) and ion exchange mechanisms (with Mn7+ ions) of Mn-DSB explained its high adsorption capacity. Therefore, this study demonstrates the potential of Mn-DSB for treating uranium-beryllium tailing wastewater.
Context. The AMS-02 and HELIX experiments should soon provide 10Be/9Be cosmic-ray data of unprecedented precision. Aims. We propose an analytical formula to quickly and accurately determine L from ...these data. Methods. Our formula is validated against the full calculation performed with the propagation code USINE. We compare the constraints on L set by Be/B and 10Be/9Be, relying on updated sets of production cross-sections. Results. The best-fit L from AMS-02 Be/B data is shifted from 5 kpc to 3.8 kpc when using the updated cross-sections. We obtained consistent results from the Be/B analysis with USINE, L = 3.8−1.6+2.8 kpc (data and cross-section uncertainties), and from the analysis of 10Be/9Be data with the simplified formula, L = 4.7 ± 0.6 (data uncertainties) ±2 (cross-section uncertainties) kpc. The analytical formula indicates that improvements on L thanks to future data will be limited by production cross-section uncertainties, unless either 10Be/9Be measurements are extended up to several tens of GeV/n, or nuclear data for the production of 10Be and 9Be are improved; new data for the production cross section of 16O into Be isotopes above a few GeV/n are especially desired.
Reconstructing Cenozoic history of continental silicate weathering is crucial for understanding Earth's carbon cycle and greenhouse history. The question of whether continental silicate weathering ...increased during the late Cenozoic, setting the stage for glacial cycles, has remained controversial for decades. Whereas numerous independent proxies of weathering in ocean sediments (e.g., Li, Sr, and Os isotopes) have been interpreted to indicate that the continental silicate weathering rate increased in the late Cenozoic, beryllium isotopes in seawater have stood out as an important exception. Beryllium isotopes have been interpreted to indicate stable continental weathering and/or denudation rates over the last 12 Myr. Here we present a Be cycle model whose results show that variations in the
Be weathering flux are counterbalanced by near-coastal scavenging while the cosmogenic
Be flux from the upper atmosphere stays constant. As a result, predicted seawater
Be/
Be ratios remain nearly constant even when global denudation and Be weathering rates increase by three orders of magnitude. Moreover,
Be/
Be records allow for up to an 11-fold increase in Be weathering and denudation rates over the late Cenozoic, consistent with estimates from other proxies. The large increase in continental weathering indicated by multiple proxies further suggests that the increased CO
consumption by continental weathering, driven by mountain-building events, was counterbalanced by other geological processes to prevent a runaway icehouse condition during the late Cenozoic. These processes could include enhanced carbonate dissolution via pyrite weathering, accelerated oxidation of fossil organic carbon, and/or reduced basalt weathering as the climate cooled.
Beryllium-containing sludge (BCS) is a byproduct of the physicochemical treatment of beryllium smelting wastewater. The pollutant element beryllium within BCS is highly unstable and extremely toxic, ...characterized by its small ionic radius and low charge density, resulting in a high risk of leaching and migration. This study is the first to investigate the leaching behavior, influencing mechanisms, and kinetic processes of beryllium in BCS under various environmental conditions. The results indicate that, under national standard conditions, beryllium exhibits a rapid leaching phase within the first 5 h, which then stabilizes after 10 h, with the total leached content significantly exceeding the leaching toxicity identification standards. Under mildly acidic (pH ≤ 5) or highly alkaline (pH = 14) conditions, beryllium demonstrates pronounced leaching and migration behaviors. Notably, in acidic conditions, the leaching rate exceeds 80% within 5 h. Combining the treatment process of beryllium-containing wastewater with analytical methods such as SEM, XPS, ToF-SIMS, and FTIR, it is revealed that due to the heterogeneous nature of BCS, the particle aggregates dissociate over time under acidic conditions. The particle surfaces become increasingly rough, leading to dissolution and the emergence of more reactive sites, resulting in a high proportion of beryllium leaching. Under these conditions, the gradual reaction of Be(OH)2 in BCS to form soluble Be2+ and its hydrolytic complexes is identified as the primary mechanism for extensive beryllium migration. The process encounters minimal diffusion resistance and is classified as reaction-controlled. In acidic conditions with pH = 4, the leaching rate of beryllium significantly increases with rising temperature. The leaching kinetics equation is (1−x)−0.44=e(18.26−53050RT)·t, with an apparent activation energy of 53.05 kJ mol−1.
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•Beryllium sludge shows high leaching at pH = 3, hinting acid rain's impact on BCS.•Be leaching kinetics at acidity: (1−x)−0.44=e(18.26−53050RT)·t, Eₐ = 53.05 kJ/mol.•Acid leaching transforms particle surfaces, causing significant calcium loss.•Be2+ solubility and hydrolysis key to its large migration, driven by reaction control.
•Potential needs in Be for fusion power engineering may exceed Be resources.•Be recycling after its operation in a fusion power plant (FPP) seems inevitable.•U impurity in Be seriously impairs ...environmental properties of fusion power plants.•Upon burial of irradiated Be the main problems are caused by U and 3H impurities.•Clearance of Be extracted from a FPP is impossible due to U impurity.
Worldwide identified resources of beryllium somewhat exceed 80 000t. Beryllium production in all the countries of the world in 2012 was about 230t. At the same time, some conceptual designs of fusion power reactors envisage utilization of several hundred tons of this metal. Therefore return of beryllium into the production cycle (recycling) will be necessary. The beryllium ore from some main deposits has uranium content inadmissible for fusion reactors. This fact raises a question on the need to develop and apply an economically acceptable technology for beryllium purification from the uranium. Practically any technological procedure with beryllium used in fusion reactors requires its detritiation. A study of tritium and helium release from irradiated beryllium at different temperatures and rates of temperature increase was performed at Kurchatov Institute.
