Rebecca K. Toghiani

Vapor-liquid equilibria for methyl tert-butyl ether + methanol and tert-amyl methyl ether + methanol

Vapor-liquid equilibrium data are reported for the binary systems MTBE/methanol and TAME/methanol. These data were obtained using a modified Stage-Muller equilibrium still. For the MTBE/methanol system, isobaric data at 53.33 and 101.33 kPa are given as are isothermal data at 313.15 and 333.15 K. Results at 101.33 kPa are in excellent agreement with available literature data. For the TAME/methanol system, isothermal data at 333.15 and 343.15 K are reported. A search of the literature revealed no isothermal data available for the TAME/methanol binary pair. Pure component vapor pressures were measured in the same apparatus and correlated using the Antoine equation.

Studies on the Gibbsite to Boehmite Transition

Abstract The transition of gibbsite to boehmite is of interest with regard to high level waste processing associated with the Hanford and Savannah River sites. Both materials have been observed in core samples. From the temperature histories of the waste, it is possible that some fraction of gibbsite has been converted to boehmite. This paper describes thermal gravimetric analysis studies of products resulting from controlled temperature measurements of pure gibbsite in NaOH. Results indicate that the gibbsite to boehmite transformation can take place at temperatures as low as 100°C. This information, along with available data on waste inventories and temperature histories, may be used to estimate the fractions of gibbsite and of boehmite in a given waste tank. Site engineers can then tailor the sludge leaching process for a particular tank to account for the delayed dissolution of boehmite, allowing separation of the aluminum and processing as a low activity waste.

SRS Low‐Curie Process Modeling and Experiments

Abstract Engineers at SRS are evaluating the Low‐Curie Salt Process which is aimed at initially withdrawing the interstitial liquor followed by dissolution of the salt cake. Partitioning of the cesium is predominantly within the interstitial liquor; consequently a separation based on activity can be effected. Laboratory experiments using simulants from SRS tanks have been performed along with thermodynamic simulations. Results indicate that insoluble layers such as Al(OH)3 and/or cancrinite may form and hinder the dissolution processes. The effectiveness of the Low‐Curie Salt Process may be reduced based on layer formation and the distribution of the interstitial liquor within the waste.