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The structures of tris(2,2'-bipyridine)cobalt(II) dichloride-2-water-ethanol, [Co/CioHjNj^jClj^HjO^HjOH (1), and tris(2,2'-bipyridine)cobalt(I) chloride-water, Co(C10H8N2)3ChH2O (2), have been determined in order to compare bonding of the high-spin d7 and high-spin d8 configurations and to better understand the electron-transfer reactivity of this couple. Compound 1 crystallizes in the hexagonal crystal system, space group P6S22, with a = 13.403 (2) Á, c = 62.566 (10) Á, and Z = 12. The structure refined to a final R value of 0.056. The coordination sphere consists of the six nitrogen atoms of the three bipyridine ligands in an octahedral arrangement about the cobalt with an average Co-N bond length of 2.128 (8) Á. One of the chloride ions is surrounded by twelve C-H-Cl hydrogen bonds involving the H3 and H3' protons on the bipyridine ligands. Compound 2 crystallizes in the orthorhombic crystal system, space group Pna2u with a = 9.713 (6) Á, b = 21.666 (10) Á, c = 13.062 (7) A, and Z = 4. The structure refined to a final R value of 0.084. The geometry of the coordination sphere of 2 is almost identical with that of 1, with an average Co-N bond length of 2.11 (2) A. Hydrogen bonding between the H3 and H3' protons on the bipyridine ligand and the chloride ion is also observed in 2. The C-H-Cl hydrogen bonding observed in these complexes and the bond length changes in 1, 2, and tris(2,2'-bipyridine)cobalt(III) are discussed and related to electron-transfer barriers for the series.

Integrating thermochemical conversion (TCC) technologies with current animal waste treatment practices can treat and reduce quantities of manure from consolidated animal feeding operations. Additionally, TCC technologies can produce value-added, renewable energy products. These products can meet heating and power needs or be catalytically converted into liquid fuels. The primary objectives of this study were to assess opportunities and obstacles in the treatment and energy conversion using currently available TCC processes. Both dry and wet livestock manures were assessed. Dry wastes like poultry litter and feedlot manures can be processed directly via pyrolysis and air/steam gasification technology. The solids in the aqueous waste streams from dairy and swine operations can undergo wet gasification or direct liquefaction processes. Alternatively, these solids can be separated and dried before conversion. Due to high ash and sulfur contents, pretreatment of manure is necessary to prevent catalyst poisoning and promote effective unit operation. While the energy input requirements for a conceptual wet gasification manure treatment system of a model swine farm is larger than a traditional anaerobic digestion operation, there are many significant advantages in implementing TCC technology including the following:  compact design; faster treatment times; reduction of odors, BOD, and pharmaceutically activated compounds; and elimination of sludge.