Zirconium zerovalent

The addition of zirconium to activated carbon may substantially increase the removal of arsenic from water (Daus, Wennrich and Weiss, 2004 Schmidt et al., 2008). (Daus, Wennrich and Weiss, 2004) used batch and column tests to evaluate the ability of five materials (activated carbon, zirconium-loaded activated carbon, zerovalent iron, granulated Fe(III) hydroxide, and a commercial product, Absorptionsmittel 3 ) to sorb As(III) and As(V) from water. The GAC had grain sizes between 1.0 and 1.5 mm. The material was primarily chosen as a comparison with the zirconium-loaded sample. The zirconium-loaded activated carbon contained 28 mg zirconium g 1 activated carbon and was produced by shaking activated carbon in a solution of zirconyl nitrate (Zr0(N03)2). The zerovalent iron (Fe(0)) primarily had particle sizes of 1.2-1.7 mm. Absorptionsmittel 3 is a mixture of calcite, brucite, fluorite, and iron hydroxides. The granular iron hydroxides consisted of mostly amorphous Fe(III) hydroxide coatings on sand grains (particle sizes of 3-4mm) (Daus, Wennrich and Weiss, 2004, 2950). 

A few examples of zerovalent zirconium and hafiiium complexes are known. The reduction of MCI4 with lithium... 

EPR spectroscopy has been used as a probe to examine the mechanism of the titanocene-catalysed dehydrocoupling of silanes in the presence of phosphines - a number of deconq)ositi(m products which derive from intermediate silyl phosphine complexes have been characterised on this basis. Zerovalent titanium, zirconium and halfium complexes of the type C5R3)M(CO)4l and related derivatives have been prepared by alkali metal naphthalide reduction followed by carbonylation. The related [Cp Hf(CO)4] complex has also been isolated and the... 

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