LCA/LCC analysis of starting-lighting-ignition lead-acid battery in China

Background China has the largest lead–acid battery (LAB) industry and market around the world, and this situation causes unavoidable emissions of Pb and other pollutants. Methods On the basis of a field survey on a starting–lighting–ignition (SLI) LAB plant in Zhejiang Province, this study applies life cycle assessment (LCA) and life cycle costing (LCC) methods to assess the environmental impacts and environment-related costs derived from the LAB industry during the life phases, including material preparation, battery assembly, transportation, and regeneration of the plant. Results Material preparation and regeneration phases contribute 3.4 and 42.2 g to Pb emission, respectively, and result in 3.29 × 108 CHY of environmental cost for each function unit (1 KVA h LAB capacity). The material preparation phase is the largest mass contributor to global warming potential (GWP, 97%), photo-chemical oxidation potential (POCP, 88.9%), and eutrophication potential (EP, 82.5%) and produces 2.68 × 108 CHY of environmental cost. Discussion Decision makers in the Chinese LAB industry should replace the pyrogenic process in smelting with the use of clean energy, increase the lead recovery rate while producing the same capacity of LABs, and develop new technologies to reduce heavy metal emission, especially in the regeneration phase

A diuranium carbide cluster stabilized inside a C80 fullerene cage.

Unsupported non-bridged uranium-carbon double bonds have long been sought after in actinide chemistry as fundamental synthetic targets in the study of actinide-ligand multiple bonding. Here we report that, utilizing Ih(7)-C80 fullerenes as nanocontainers, a diuranium carbide cluster, U=C=U, has been encapsulated and stabilized in the form of UCU@Ih(7)-C80. This endohedral fullerene was prepared utilizing the Krätschmer-Huffman arc discharge method, and was then co-crystallized with nickel(II) octaethylporphyrin (NiII-OEP) to produce UCU@Ih(7)-C80·[NiII-OEP] as single crystals. X-ray diffraction analysis reveals a cage-stabilized, carbide-bridged, bent UCU cluster with unexpectedly short uranium-carbon distances (2.03 Å) indicative of covalent U=C double-bond character. The quantum-chemical results suggest that both U atoms in the UCU unit have formal oxidation state of +5. The structural features of UCU@Ih(7)-C80 and the covalent nature of the U(f1)=C double bonds were further affirmed through various spectroscopic and theoretical analyses

Foreword to the special virtual issue on Actinide physics and chemistry with synchrotron radiation

Foreword to the virtual special issue of Journal of Synchrotron Radiation on Actinide Physics and Chemistry with Synchrotron Radiation

The first actinide polyiodate: a complex multifunctional compound with promising X-ray luminescence properties and proton conductivity

Herein we report the first example of an actinide polyiodate compound, namely K4[(UO2)2(IO3)6(I4O11)]·(HIO3)4(H2O)6 (UPI-1), which was obtained from slow evaporation of nitric acid with a high I/U ratio. Spectroscopic measurements indicate that UPI-1 possesses X-ray luminescence properties applicable for X-ray scintillation and also exhibits modest protonic conduction

Identification of a uranium-rhodium triple bond in a heterometallic cluster

International audienceThe chemistry of d-block metal-metal multiple bonds has been extensively investigated in the past 5 decades. However, the synthesis and characterization of species with f-block metal-metal multiple bonds are significantly more challenging and such species remain extremely rare. Here, we report the identification of a uranium-rhodium triple bond in a heterometallic cluster, which was synthesized under routine conditions. The uranium-rhodium triple-bond length of 2.31 angstrom in this cluster is only 3% longer than the sum of the covalent triple-bond radii of uranium and rhodium (2.24 angstrom). Computational studies reveal that the nature of this uranium-rhodium triple bond is 1 covalent bond with 2 rhodium-to-uranium dative bonds. This heterometallic cluster represents a species with f-block metal-metal triple bond structurally authenticated by X-ray diffraction. These studies not only demonstrate the authenticity of the uranium-metal triple bond, but also provide a possibility for the synthesis of other f-block metal-metal multiple bonds. We expect that this work may further our understanding of the bonding between uranium and transition metals, which may help to design new d-f heterometallic catalysts with uranium-metal bonds for small-molecule activation and to promote the utilization of abundant depleted uranium resources

Extreme condition high temperature and high pressure studies of the K–U–Mo–O system

Herein the first examples of alkali earth uranyl molybdates synthesised using extreme conditions of high temperature and high pressure (HT/HP) methods, namely K2[UO2(Mo2O7)2], K2[(UO2)2(Mo(vi)4Mo(iv)(OH)2)O16], K3[(UO2)6(OH)2(MoO4)6(MoO3OH)] and K5[(UO2)10MoO5O11OH]·H2O, are described and characterised. K2[UO2(Mo2O7)2] forms a monoclinic 2D layered structure in space group P21/c that consists of interlinking Mo2O7 dimers that link isolated UO22+ moieties forming [UO2(Mo2O7)2]2- layers which are separated by K+ cations. K2[(UO2)2(Mo(vi)4Mo(iv)(OH)2)O16] forms a disordered triclinic 3D framework structure in space group P1. The structure consists of isolated UO22+ moieties connected in a layered configuration via Mo(vi)O6 polyhedra of which the layers are bridged by Mo(iv)O6 polyhedra that are partially positionally disordered by charge balancing K+ and bridging Mo4+ cations. K3[(UO2)6(OH)2(MoO4)6(MoO3OH)] adopts a disordered orthorhombic 3D framework structure in space group Pbcm consisting of small channels and large cavities built upon corner sharing MoO4 and UO22+ moieties that respectively encapsulate ordered and disordered K+ cations. K5[(UO2)10MoO5O11OH]·H2O forms a triclinic 3D framework structure in space group P1 consisting of interlinking UO6, UO7 and MoO5 polyhedra which utilise cation-cation interactions between UO22+ moieties to create infinite channels parallel to the [001] direction which contain partially disordered K+ cations and H2O molecules. A combination of single crystal X-ray diffraction, bond valence sums calculations and scanning electron microscopy with energy dispersive X-ray spectroscopic measurements was used to characterise all obtained samples in this investigation. The structures uncovered in this investigation are discussed systematically in detail with other members of the broader A+-U-Mo-O system from the literature where the relationship between the degree of pressure applied and U/Mo ratio used during synthesis on the ability to obtain high dimensional structures via condensation and oligomerization of polyhedra is identified and discussed in detail

Transition-metal-bridged bimetallic clusters with multiple uranium-metal bonds

International audienceHeterometallic clusters are important in catalysis and small-molecule activation because of the multimetallic synergistic effects from different metals. However, multimetallic species that contain uranium-metal bonds remain very scarce due to the difficulties in their synthesis. Here we present a straightforward strategy to construct a series of heterometallic clusters with multiple uranium-metal bonds. These complexes were created by facile reactions of a uranium precursor with Ni(COD)(2) (COD, cyclooctadiene). The multimetallic clusters' cores are supported by a heptadentate N4P3 scaffold. Theoretical investigations indicate the formation of uranium-nickel bonds in a U2Ni2 and a U2Ni3 species, but also show that they exhibit a uranium-uranium interaction; thus, the electronic configuration of uranium in these species is U(iii)-5f(2)6d(1). This study provides further understanding of the bonding between f-block elements and transition metals, which may allow the construction of d-f heterometallic clusters and the investigation of their potential applications