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Transformation of multifunctional materials with control over site-selectivity and chemical diversity remains challenging. Herein, we present a metal-free, one-pot strategy for the defluorophosphorylation of polyfluoroalkyl peroxides that enables expedient construction of structurally diverse phosphoryl-containing heterocyclic libraries. By judicious choice of reaction conditions, C 3,4-diphosphoryl furans and C 4-monophosphoryl furans can be easily accessed. In addition, synthetic derivatization of the obtained organophosphorus heteroarenes to value-added monodentate and bidentate phosphines has been demonstrated. Mechanistic studies revealed that regioselective defluorophosphorylation allows divergent product formation in two reaction modes. 

Magnetic materials were recently developed for sludge disposal because of their advantages. However, the role of magnetic materials in the process of anaerobic digestion of municipal dewatered sludge remains unclear. The aim of this present study is to investigate the magnetic effect factors such as static magnetic field, magnetic nanoparticles, and ordinary magnetic particles on the anaerobic digestion of municipal dewatered sludge. In addition, the biogas production variations and relevant physicochemical properties of municipal dewatered sludge under anaerobic digestion are also evaluated by adding anaerobic bacteria. Results indicated that the magnetic nanoparticles are superior to both ordinary magnetic particles and static magnetic field at total biogas production; moreover, the aerobic bacteria could shorten the duration of anaerobic digestion. For the sludge dewatering, the organic matter degradation rate, chemical oxygen demand degradation rate, and dewatering rate under the treatment condition with magnetic nanoparticles are 32.1%, 87.1%, and 70.9%, respectively. It is suggested that the magnetic nanoparticles are much suitable for sludge dewatering than ordinary magnetic particles. As combined with bacteria, magnetic nanoparticles can effectively increase gas output, methane content, and shorten the anaerobic digestion period. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 374–379, 2019

 

Ferrous sulfate (FeSO₄) is widely used to effectively stabilize hexavalent chromium (Cr(VI))‐contaminated soil. The leaching behavior, Cr(VI) content, and chromium speciation distribution in the stabilized soil are the most important indexes for determining the effectiveness of reduction treatment. Numerous factors, such as reductant dosage and soil particle size, affect the stabilization process; these factors are relatively important. This study investigated the influence of FeSO₄dosage and soil particle size on leachability and speciation distribution of chromium in contaminated soil. Results showed that the increase in FeSO₄significantly reduced the leachability and Cr(VI) content in the soil given the increased reducible species that stem from an acid soluble fraction of chromium. The small particle size of the soil that contains a large surface area facilitated the reaction between Cr(VI) and FeSO₄, thereby resulting in low leachability and high reducible species of Cr(VI) in the stabilized soil. The leached Cr(VI) concentration was exponentially correlated to Cr(VI) content in the stabilized soil, and the leachability of Cr from the stabilized soil was linearly correlated to the exchangeable phase of Cr. In addition, the leached Cr(VI) concentration from the stabilized soil conform to the US Environmental Protection Agency and China regulatory limits; meanwhile, considerable Cr(VI) remained in a few stabilized soil and exceeded the environmental quality standards for soil in China. These results illustrated the importance of a comprehensive assessment of Cr(VI)‐contaminated soil, which is treated by reductants for enabling flexible future land use. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 500–507, 2019