SuperLig(R) 639 ion exchange resin is currently being evaluated for technetium (Tc-99) removal from radioactive Hanford tank wastes. To assess the performance of the resin in column configuration, a multiple batch contact method was used to determine the equilibrium distribution coefficients (K-d values) and percent removal for technetium. (as pertechnetate, TcO4-) from highly alkaline waste solutions obtained from the Hanford Site. The K-d values for Hanford tank wastes AN-103, AZ-102, and AN-102 were 530, 886, and 287mL/g, respectively. The TcO4- K-d values for the AN-102 mixed with AN-103 after 4 hours and 14 days were 456 and 392mL/g, respectively. The percent removal of technetium as TcO4- anion from three Hanford tank solutions (AN-103, AZ-102, and AN-102) was higher than 80%, which is required for Hanford waste pretreatment flowsheet. The results indicate that SuperLig(R) 639 resin is highly selective for per-technetate in the presence of relatively high concentrations of nitrate anion.

The title compound, Cs+[Co((3)-1,2-C2B9H11)2]− (CsCDC), was precipitated with a NaCDC solution from solutions containing CsCl. The reaction was followed by measuring the loss of light intensity as the precipitate formed. [Cs+] and [CDC−] at the point of precipitation were estimated and approximate values of Ksp for CsCDC were determined at room temperature: 8 × 10−6 (water), 7 × 10−6 (1 M NaOH) and 2 × 10−6 (5M NaCl/0.1 M KOH/1.0 M NaOH). In some cases, NaCDC precipitated from solution when added to the latter salt solution. For the medium, 5 M NaNO3/0.1 M KOH/1.0 M NaOH, a four-fold excess of NaCDC was added to a 10 mM Cs+ solution at 40°C and the [CDC−] measured spectrophotometrically. Only CsCDC precipitated, and a Ksp of 3.9 × 10−6 was determined. The solubilities of CsCDC were measured in NaNO3 and NaCl solutions at 30°C as a function of the Na salt concentration. The reaction of the CDC− with OH− slowly produces B(OH)4−, H2 and CoO(OH). The reaction of 22 μM CsCDC 173 with NaOH (1 M) has a first-order rate constant at 56°C of 8.8 × 10−7 s−1, while that for NaCDC (14 mM) is 7.2 × 10−7 s−1. The activation energy for the reaction is 110 kJ mol−1.

AbstractReview: (The Chemistry of Heteronuclear Clusters and Multimetallic Catalysts; Proceedings of the Seminar in Koenigstein, Sept.

The clusters, CP2′Mo2Fe2S2(CO)8 (MoFeS) and Cp2′Mo2CO2S3(CO)4 (MoCoS) (Cp′ = η-C5H4Me) have been supported on the refractory oxides, Al2O3, SiO2, TiO2, and MgO, and subjected to temperature programmed decomposition (TPDE) under flowing H2. Typically, CO evolution commences near 100°C, followed by evolution of 1–2 Cp-ligands from 180 to 400°C along with small amounts of CO2, CH4, and H2S or Me2S. The resulting compositions are shown to be active catalysts for CO hydrogenation and hydrodesulphurization (HDS) of thiophene. Methane is the principal hydrocarbon product from CO hydrogenation except for MoFeS/MgO where high selectivity for C2 products was observed. The activity and selectivity of MoCoS/Al2O3 for thiophene HDS closely resembles those of conventionally prepared “cobalt molybdate” catalysts. The cluster derived catalysts have been characterized by Mössbauer and X-ray absorption (XANES) and EXAFS) spectroscopies. It is concluded that the clusters undergo oxidation by the surface upon loss of organic ligands.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactivity and structure of a cationic allenyl complex, (.mu.-.eta.2,.eta.3-allenyl)bis(methylcyclopentadienyl)tetracarbonyldimolybdenum tetrafluoroborate, and its reductive coupling product, [Cp2(CO)4Mo2]2-.mu.-(.mu.-HC.tplbond.CCH2)2Angelika Meyer, Daniel J. McCabe, and M. David CurtisCite this: Organometallics 1987, 6, 7, 1491–1498Publication Date (Print):July 1, 1987Publication History Published online1 May 2002Published inissue 1 July 1987https://pubs.acs.org/doi/10.1021/om00150a021https://doi.org/10.1021/om00150a021research-articleACS PublicationsRequest reuse permissionsArticle Views82Altmetric-Citations66LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts