Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division: January-March 1999

This reports summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period January--March 1999. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within eight major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Separations and Materials Synthesis, Fluid Structure and Properties, Biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information. Activities conducted within the area of Hot Cell Operations included column loading of cesium from Melton Valley Storage Tank supematants using an engineered form of crystalline silicotitanate. A second task was to design and construct a continuously stirred tank reactor system to test the Savannah River-developed process of small-tank tetraphenylborate precipitation to remove cesium, strontium, and transuranics from supematant. Within the area of Process Chemistry and Thermodynamics, the problem of solids formation in process solutions from caustic treatment of Hanford sludge was addressed, including issues such as pipeline plugging and viscosity measurements. Investigation of solution conditions required to dissolve Hanford saltcake was also continued. MSRE Remediation Studies focused on recovery of {sup 233}U and its transformation into a stable oxide and radiolysis experiments to permit remediation of MSRE fuel salt. In the area of Chemistry Research, activities included studies relative to molecular imprinting for use in areas such as selective sorption, chemical sensing, and catalysis, as well as spectroscopic investigation into the fundamental interaction between ionic solvents and solutes in both low- and high-temperature ionic liquids. In the area of Separations and Materials Synthesis, fundamental studies explored the use of electromagnetic fields to enhance transport processes in multiphase separations; investigated nucleation and particle growth for the synthesis, characterization, application, and processing of ultrafine particles; and examined the use of electric fields to modify phase equilibria in multiphase separations processes. Other efforts involved enhanced oxidation of organic pollutants in aqueous solutions by applying electric fields to form microbubbles and the use of electric fields to improve distillation efficiency. Research was also directed toward the use of ozonation to treat water-soluble organics, the application of electrical and acoustic methods to remediate aerosol problems, and the development of improved means of decontamination using aqueous surfactant cleaners. Fluid Structure and Properties included molecular-based studies of systems with supercritical solvents, a multi-institutional initiative to develop a molecular understanding of reverse miscelles in supercritical carbon dioxide through experimentation and molecular simulation calculations, and molecular-based prediction of the structure and properties of long-chain molecules undergoing shear flow