Beryllium is an important industrial metal because of its unusual material properties: it is lighter than aluminum and six times stronger than steel. Often alloyed with other metals such as copper, beryllium is a key component of materials used in the aerospace and electronics industries. Beryllium has a small neutron cross-section, which makes it useful in the production of nuclear weapons and in sealed neutron sources. Unfortunately, beryllium is one of the most toxic elements in the periodic table. It is responsible for the often-fatal lung disease, Chronic Beryllium Disease (CBD) or berylliosis, and is listed as a Class A EPA carcinogen. Coal-fired power plants, industrial manufacturing and nuclear weapons production and disposal operations have released beryllium to the environment. This contamination has the potential to expose workers and the public to beryllium. Despite the increasing use of beryllium in industry, there is surprisingly little published information about beryllium fate and transport in the environment. This information is crucial for the development of strategies that limit worker and public exposure. This review summarizes the current understanding of beryllium health hazards, current regulatory mandates, environmental chemistry, geochemistry and environmental contamination.

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We have studied the photochemical reduction of uranyl to generate UO2 without hydrogen reduction. Formate and oxalate were examined as potential reductants that only lead to CO2 production as a side product. Despite the similar nature of the two reductants, the mechanism for quenching the uranyl excited-state changes drastically and leads to dramatically different chemistry at low pH. Oxalate quenches by unimolecular electron transfer and formate quenches by H-atom abstraction. Because of the change in mechanism, photochemical reduction of uranyl with formate works with high efficiency at low pH while photolysis in the presence of oxalate leads to the generation of CO and no net uranyl reduction. Photochemical reduction of uranyl with formate at low pH leads to U(IV) in solution that can then be precipitated as UO2 by simply raising the pH with yields as high as 99.992%.

We report the rational design of ligands that selectively bind beryllium. We selected two ligands to design Be based on binding polynulear species with a Be-O-Be motif: 2-hydroxyisophthalic acid (HIPA) and 2,3-dihydroxybenzoic acid (DHBA). All previous work has focused on BeL or BeL2 species. The HIPA and DHBA have extremely high binding constants of 17.5 and 18.4, respectively. These ligands outcompete chromotropic acid, which has one the highest binding constants for Be reported in the literature for a simple BeL species. The binding of the second Be to form the Be-O-Be motif is so strong that polynuclear species predominates in solution down to micromolar concentrations. Both ligands show a fluorescence response in the presence of beryllium, making them promising candidates for fluorescence-based sensors. In the case of HIPA, there is a fluorescence shift, and in the case of DHBA, the presence of beryllium turns on the fluorescence by removing two OH bonds that otherwise lead to nonradiative decay. The most dramatic result is that DHBA selectively binds Be in the presence of a metal cocktail containing a 50-fold excess of Al, Fe, Cr, Cu, Zn, Cd, and Pb. This is the first time that such selectivity for beryllium has been demonstrated.

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