Chit Than

Mathematical comparison of three tritium system effluent HTO cleanup systems

ABSTRACT It is important that air emissions from tritium systems be kept as low as reasonably achievable. Thus, over the years a number of gas detritiation systems have been developed. Recently there has been interest in lower-cost, simpler systems which do not convert HT to the much more hazardous HTO form. Examples of such systems are 1) a bubbler/dehumidifier, 2) a bubbler/collector, and 3) an adsorber/collector. A computer model of each configuration was written and run. Each system’s performance, including tritium buildup in liquid water, and tritium exhausted to the environment, are presented and compared.

Homogeneous and heterogeneous metal-catalysed hydrogen isotope exchange of nitrobenzene with tritium gas and tritiated water

Hydrogen isotope exchange of nitrobenzene with tritium gas and tritiated water is studied over heterogeneous and homogeneous forms of platinum, palladium and nickel. Exchange with water is facile where homogeneous platinum and palladium salts are the catalysts but this is not the case over heterogeneous forms of the metals. In contrast, exchange with tritium gas is facile over heterogeneous platinum, palladium and nickel. Exchange in nitrobenzene is thus an indicator of homogeneous, as distinct from heterogeneous, exchange as previously claimed, only where the isotope source is water and not elemental hydrogen. Detailed isotope orientation patterns, determined by 3H NMR, are interpreted in terms of the type of absorption intermediate on the metal, and compared with those of aniline.

Catalytic Oxidation of Methane Over Alpo4-5 and Metal – Doped Alpo4-5

Abstract The catalytic oxidation of methane over AlPO4-5 and metal – doped AlPO4-5 has been studied over a range of temperatures (500–900°C) and O2 : CH4 ratios. The major products of the reaction were ethane, ethene, CO2 and H2O. The product distribution was found to be dependent on both temperature and O2 : CH4 Doping of AlPO4-5 with various metals (Pt, Pb, V, Ag, Co, Cu) altered the product distribution, with PbAlPO4-5 the most reactive and selective supported metal catalyst for methane oxidation.

Hydrogen isotope labelling of organic compounds catalysed by microporous aluminophosphates: specificity of tritium gas exchange

Microporous aluminophosphate (ALPO) catalysts are shown to have high activity and unique specificity for exchange between elemental tritium gas and both aromatic and branched aliphatic compounds, suggesting their applicability as catalysts in a range of other reactions.